Prove that w is a subspace of v

The theorem: Let U, W U, W are subspaces of V. Then U + W U + W is a direct sum U ∩ W = {0} U ∩ W = { 0 }. The proof: Suppose " U + W U + W is a direct sum" is true. Then v ∈ U, w ∈ W v ∈ U, w ∈ W such that 0 = v + w 0 = v + w. And since U + W U + W is a direct sum v = w = 0 v = w = 0 by the theorem "Condition for a direct sum".

Prove that w is a subspace of v. Sep 17, 2022 · Definition 6.2.1: Orthogonal Complement. Let W be a subspace of Rn. Its orthogonal complement is the subspace. W ⊥ = {v in Rn ∣ v ⋅ w = 0 for all w in W }. The symbol W ⊥ is sometimes read “ W perp.”. This is the set of all vectors v in Rn that are orthogonal to all of the vectors in W.

We claim that S is not a subspace of R4. If S is a subspace of R4, then the zero vector 0 = [0 0 0 0] in R4 must lie in S. However, the zero vector 0 does not satisfy the equation. 2x + 4y + 3z + 7w + 1 = 0. So 0 ∉ S, and we conclude that S is not subspace of R4.

Theorem 1.3. The span of a subset of V is a subspace of V. Lemma 1.4. For any S, spanS3~0 Theorem 1.5. Let V be a vector space of F. Let S V. The set T= spanS is the smallest subspace containing S. That is: 1. T is a subspace 2. T S 3. If W is any subspace containing S, then W T Examples of speci c vector spaces. P(F) is the polynomials of coe ...2 be subspaces of a vector space V. Suppose W 1 is neither the zero subspace {0} nor the vector space V itself and likewise for W 2. Show that there exists a vector v ∈ V such that v ∈/ W 1 and v ∈/ W 2. [If a subspace W = {0} or V, we call it a trivial subspace and otherwise we call it a non-trivial subspace.] Solution. If W 1 ⊆ W 2 ... Prove: If W⊆V is a subspace of a finite dimensional vector space V then W is finite dimensional. This problem has been solved! You'll get a detailed solution from a subject matter expert that helps you learn core concepts.The clases $\{ v_{r+1} + W, \dots, v_n + W \}$ are a basis of the quotient space (Why?) A proof of the dimension now follows easily. A proof of the dimension now follows easily. Since you ask for another proof.A subset W of a vector space V is called a subspace of V if W is itself a vector space under the addition and scalar multiplication defined on V. In general, one must verify the ten vector space axioms to show that a set W with addition and scalar multiplication 5 forms a …Verify that \(V\) is a subspace, and show directly that \(\mathcal{B}\) is a basis for \(V\). Solution. First we observe that \(V\) is the solution set of the homogeneous equation \(x + 3y + z = 0\text{,}\) so it is a subspace: see this note in Section 2.6, Note 2.6.3. To show that \(\mathcal{B}\) is a basis, we really need to verify three things:

Similarly, we have ry ∈ W2 r y ∈ W 2. It follows from this observation that. rv = r(x +y) = rx + ry ∈ W1 +W2, r v = r ( x + y) = r x + r y ∈ W 1 + W 2, and thus condition 3 is met. Therefore, by the subspace criteria W1 +W2 W 1 + W 2 is a subspace of V V.Jan 11, 2020 · Yes, exactly. We know by assumption that u ∈W1 u ∈ W 1 and that u + v ∈W1 u + v ∈ W 1. Since W1 W 1 is a subspace of V V, it is closed under taking inverses and under addition, thus −u ∈ W1 − u ∈ W 1 (because u ∈ W1 u ∈ W 1) and finally −u + (u + v) = v ∈ W1 − u + ( u + v) = v ∈ W 1. Share Cite Follow answered Jan 11, 2020 at 7:17 Algebrus 861 4 14 If you’re a taxpayer in India, you need to have a Personal Account Number (PAN) card. It’s crucial for proving your identify and proving that you paid your taxes that year. Here are the steps you can take to apply online.A subset W ⊆ V is said to be a subspace of V if a→x + b→y ∈ W whenever a, b ∈ R and →x, →y ∈ W. The span of a set of vectors as described in Definition 9.2.3 is an example of a subspace. The following fundamental result says that subspaces are subsets of a vector space which are themselves vector spaces.m is linearly independent in V and w 2V. Show that v 1;:::;v ... and U is a subspace of V such that v 1;v 2 2U and v 3 2= U and v 4 2= U, then v 1;v 2 is a basis of U ...Mar 1, 2015 · If x ∈ W and α is a scalar, use β = 0 and y =w0 in property (2) to conclude that. αx = αx + 0w0 ∈ W. Therefore W is a subspace. QED. In some cases it's easy to prove that a subset is not empty; so, in order to prove it's a subspace, it's sufficient to prove it's closed under linear combinations. The column space and the null space of a matrix are both subspaces, so they are both spans. The column space of a matrix A is defined to be the span of the columns of A. The null space is defined to be the solution set of Ax = 0, so this is a good example of a kind of subspace that we can define without any spanning set in mind. In other words, it is …

Yes, because since $W_1$ and $W_2$ are both subspaces, they each contain $0$ themselves and so by letting $v_1=0\in W_1$ and $v_2=0\in W_2$ we can write $0=v_1+v_2$. Since $0$ can be written in the form $v_1+v_2$ with $v_1\in W_1$ and $v_2\in W_2$ it follows that $0\in W$. Definition. If V is a vector space over a field K and if W is a subset of V, then W is a linear subspace of V if under the operations of V, W is a vector space over K.Equivalently, a nonempty subset W is a linear subspace of V if, whenever w 1, w 2 are elements of W and α, β are elements of K, it follows that αw 1 + βw 2 is in W. Oct 8, 2019 · So, in order to show that this is a member of the given set, you must prove $$(x_1 + x_2) + 2(y_1 + y_2) - (z_1 + z_2) = 0,$$ given the two assumptions above. There are no tricks to it; the proof of closure under $+$ should only be a couple of steps away. The moment you find out that you’re going to be a parent will likely rank in the top-five best moments of your life — someday. The truth is, once you take that bundle of joy home, things start getting real, and you may begin to wonder if th...

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Such that x dot v is equal to 0 for every v that is a member of r subspace. So our orthogonal complement of our subspace is going to be all of the vectors that are orthogonal to all of these vectors. And we've seen before that they only overlap-- there's only one vector that's a member of both. That's the zero vector.You may be confusing the intersection with the span or sum of subspaces, $\langle V,W\rangle=V+W$, which is incidentally the subspace spanned by their set-theoretic union. If you want to know why the intersection of subspaces is itself a subspace, you need to get your hands dirty with the actual vector space axioms.Answer: A A is not a vector subspace of R3 R 3. Thinking about it. Now, for b) b) note that using your analysis we can see that B = {(a, b, c) ∈R3: 4a − 2b + c = 0} B = { ( a, b, c) ∈ R 3: 4 a − 2 b + c = 0 }. It's a vector subspace of R3 R 3 because: i) (0, 0, 0) ∈ R3 ( 0, 0, 0) ∈ R 3 since 4(0) − 2(0) + 0 = 0 4 ( 0) − 2 ( 0 ...Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site

Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this siteHelp Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site1. You're misunderstanding how you should prove the converse direction. Forward direction: if, for all u, v ∈ W u, v ∈ W and all scalars c c, cu + v ∈ W c u + v ∈ W, then W W is a subspace. Backward direction: if W W is a subspace, then, for all u, v ∈ W u, v ∈ W and all scalars c c, cu + v ∈ W c u + v ∈ W. Note that the ...The clases $\{ v_{r+1} + W, \dots, v_n + W \}$ are a basis of the quotient space (Why?) A proof of the dimension now follows easily. A proof of the dimension now follows easily. Since you ask for another proof.Prove that if W is a subspace of a finite dimensional vector space V, then dim(W) ≤ dim(V). 2 Proving that $\operatorname{Ann}(W)$ is a subspace of $\operatorname{Hom}(V,F)$ and further $\dim \operatorname{Ann}(W) = \dim V-\dim W$The proof is essentially correct, but you do have some unnecessary details. Removing redundant information, we can reduce it to the following:My Linear Algebra book (Larson, Eight Edition) has a two-part exercise that I'm trying to answer. I was able to do the first [proving] part on my own but need help tackling the second part of the p...to check that u+v = v +u (axiom 3) for W because this holds for all vectors in V and consequently holds for all vectors in W. Likewise, axioms 4, 7, 8, 9 and 10 are inherited by W from V. Thus to show that W is a subspace of a vector space V (and hence that W is a vector space), only axioms 1, 2, 5 and 6 need to be verified. The

Therefore, V is closed under scalar multipliction and vector addition. Hence, V is a subspace of Rn. You need to show that V is closed under addition and scalar multiplication. For instance: Suppose v, w ∈ V. Then Av = λv and Aw = λw. Therefore: A(v + w) = Av + Aw = λv + λw = λ(v + w). So V is closed under addition.

Please Subscribe here, thank you!!! https://goo.gl/JQ8NysHow to Prove a Set is a Subspace of a Vector SpaceYes, because since $W_1$ and $W_2$ are both subspaces, they each contain $0$ themselves and so by letting $v_1=0\in W_1$ and $v_2=0\in W_2$ we can write $0=v_1+v_2$. Since $0$ can be written in the form $v_1+v_2$ with $v_1\in W_1$ and $v_2\in W_2$ it follows that $0\in W$.Prove: If W⊆V is a subspace of a finite dimensional vector space V then W is finite dimensional. This problem has been solved! You'll get a detailed solution from a subject matter expert that helps you learn core concepts.Suppose that V is a nite-dimensional vector space. If W is a subspace of V, then W if nite dimensional and dim(W) dim(V). If dim(W) = dim(V), then W = V. Proof. Let W be a subspace of V. If W = f0 V gthen W is nite dimensional with dim(W) = 0 dim(V). Otherwise, W contains a nonzero vector u 1 and fu 1gis linearly independent. If Span(fu Next we give another important example of an invariant subspace. Lemma 3. Suppose that T : V !V is a linear transformation, and let x2V. Then W:= Span(fx;T(x);T2(x);:::g) is a T-invariant subspace. Moreover, if Zis any other T-invariant subspace that contains x, then WˆZ. Proof. First we show that W is T-invariant: let y2W. We have to show ...Let $V$ be an inner product space, and let $W$ be a finite-dimensional subspace of $V$. If $x \not\in W$, prove that there exists $y \in V$ such that $y \in W^\perp ...Wi = fw„ 2 Vjw„ 2 Wi8i 2 Ig is a subspace. Proof. Let „v;w„ 2 W. Then for all i 2 I, „v;w„ 2 Wi, by deflnition. Since each Wi is a subspace, we then learn that for all a;b 2 F, a„v+bw„ 2 Wi; and hence av„+bw„ 2 W. ⁄ Thought question: Why is this never empty? The union is a little trickier. Proposition. W1 [W2 is a ... The entire problem statement is, Suppose that $V$ and $W$ are finite dimensional and that $U$ is a subspace of $V$. Prove that there exists $T\in\mathfrak{L}(V,W ...Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site

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Definition 6.2.1: Orthogonal Complement. Let W be a subspace of Rn. Its orthogonal complement is the subspace. W ⊥ = {v in Rn ∣ v ⋅ w = 0 for all w in W }. The symbol W ⊥ is sometimes read “ W perp.”. This is the set of all vectors v in Rn that are orthogonal to all of the vectors in W.To show that the W is a subspace of V, it is enough to show that. W is a subset of V. The zero vector of V is in W. For any vectors u and v in W, u + v is in W. (closure under additon) For any vector u and scalar r, the product r · u is in W. (closure under scalar multiplication).87% (15 ratings) for this solution. Step 1 of 3. For a fixed matrix, we need to prove that the set. is a subspace of . If W is a nonempty subset of a of vector space V, then W is a subspace of V if and only if the following closure conditions hold. (1) If u and v are in W, then is in W. (2) If u is in W and c is any scalar, then is in W.to check that u+v = v +u (axiom 3) for W because this holds for all vectors in V and consequently holds for all vectors in W. Likewise, axioms 4, 7, 8, 9 and 10 are inherited by W from V. Thus to show that W is a subspace of a vector space V (and hence that W is a …Sep 17, 2022 · Definition 6.2.1: Orthogonal Complement. Let W be a subspace of Rn. Its orthogonal complement is the subspace. W ⊥ = {v in Rn ∣ v ⋅ w = 0 for all w in W }. The symbol W ⊥ is sometimes read “ W perp.”. This is the set of all vectors v in Rn that are orthogonal to all of the vectors in W. A US navy ship intercepts missiles launched by Houthi rebels in Yemen. Two American bases in Syria come under fire. In Iraq, drones and rockets fired at US forces.So showing that W is subspace is equivalent to showing that T (ap+bq) = aT (p)+bT (q). In other words, W is a subspace of V iff it there exists some linear operator for which W is the null space. So part (b) comes down to finding a basis of the null space of T, and (c) follows simply by counting the number of vectors in (b).Feb 3, 2016 · To show $U + W$ is a subspace of $V$ it must be shown that $U + W$ contains the the zero vector, is closed under addition and is closed under scalar multiplication. Jun 1, 2020 · 0. If W1 ⊂ W2 W 1 ⊂ W 2 then W1 ∪W2 =W2 W 1 ∪ W 2 = W 2 and W2 W 2 was a vector subspace by assumption. In infinite case you have to check the sub space axioms in W = ∪Wi W = ∪ W i. eg if a, b ∈ W a, b ∈ W, that a + b ∈ W a + b ∈ W. But if you take a, b ∈ W a, b ∈ W there exist a Wj W j with a, b ∈ Wj a, b ∈ W j and ... In a vector space V(dim-n), prove that the set of all vectors orthogonal to any vector( not equal to 0) form a subspace V[dim: (n-1)]. I am wondering how the n-1 is coming in the in the picture? Stack Exchange Network. ….

Let B={(0,2,2),(1,0,2)} be a basis for a subspace of R3, and consider x=(1,4,2), a vector in the subspace. a Write x as a linear combination of the vectors in B.That is, find the coordinates of x relative to B. b Apply the Gram-Schmidt orthonormalization process to transform B into an orthonormal set B. c Write x as a linear combination of the vectors in B.That is, find the coordinates of x ...Yes, because since $W_1$ and $W_2$ are both subspaces, they each contain $0$ themselves and so by letting $v_1=0\in W_1$ and $v_2=0\in W_2$ we can write $0=v_1+v_2$. Since $0$ can be written in the form $v_1+v_2$ with $v_1\in W_1$ and $v_2\in W_2$ it follows that $0\in W$. If V is a vector space over a field K and if W is a subset of V, then W is a linear subspace of V if under the operations of V, W is a vector space over K. Equivalently, a nonempty subset W is a linear subspace of V if, whenever w1, w2 are elements of W and α, β are elements of K, it follows that αw1 + βw2 is in W. [2] [3] [4] [5] [6] Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site(a)For any X V, the set spanXis a subspace of V. (b)The map taking a subset Xof V to the set spanXis a closure operator on V. (c)If W is a subspace of V which contains a set X, then W also contains the subspace spanX. Problem 8. Let Xbe a nonempty subset of a vector space V. Assume v is a vector in the span of X, butSuppose that V is a nite-dimensional vector space. If W is a subspace of V, then W if nite dimensional and dim(W) dim(V). If dim(W) = dim(V), then W = V. Proof. Let W be a subspace of V. If W = f0 V gthen W is nite dimensional with dim(W) = 0 dim(V). Otherwise, W contains a nonzero vector u 1 and fu 1gis linearly independent. If Span(fu Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.. Visit Stack ExchangeGiven the subset $W$ of the vector space $V$, call $A(W)$ = {$\phi\in V^* | \phi$ annihilates $W$} the annihilator of $W$. Show that $A(W)$ is a subspace of $V^*$.And it is always true that span(W) span ( W) is a vector subspace of V V. Therefore, if W = span(W) W = span ( W), then W W is a vector subspace of V V. On the other hand, if W W is a vector subspace of V V, then, since span(W) span ( W) is the smallest vector subspace of V V containing W W, span(W) = W span ( W) = W. Share. Prove that w is a subspace of v, To check that a subset \(U\) of \(V\) is a subspace, it suffices to check only a few of the conditions of a vector space. Lemma 4.3.2. Let \( U \subset V \) be a subset of a vector space \(V\) over \(F\). Then \(U\) is a subspace of \(V\) if and only if the following three conditions hold. additive identity: \( 0 \in U \); , Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site, We see in the above pictures that (W ⊥) ⊥ = W.. Example. The orthogonal complement of R n is {0}, since the zero vector is the only vector that is orthogonal to all of the vectors in R n.. For the same reason, we have {0} ⊥ = R n.. Subsection 6.2.2 Computing Orthogonal Complements. Since any subspace is a span, the following proposition gives a recipe for …, Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site, Jun 15, 2018 · Let $F:V\rightarrow U$ be a linear transformation. We have to show that the preimage of any subspace of $U$ is a subspace of $V$. My proof: Say $W$ is a subspace of ... , 2012年12月4日 ... If we now assume that all the diagonal block spaces are algebras, then we prove that W contains a non-singular matrix, which yields, as ..., Sep 13, 2015 · Well, let's check it out: a. $$0\left[ \begin{array}{cc} a & b \\ 0 & d \\ \end{array} \right] = \left[ \begin{array}{cc} 0 & 0 \\ 0 & 0 \\ \end{array} \right]$$ Yep ... , 2;W are subspaces of V such that V = U 1 W and V = U 2 W then U 1 = U 2. Counterexample. Let V = R2. Let W be the x-axis. That is, W = f(x;0) jx 2Rg This is a subspace: If we set x = 0, we see that (0;0) 2W. And if we take (x 1;0)+(x 2;0) = (x 1 +x …, Jun 15, 2018 · Let $F:V\rightarrow U$ be a linear transformation. We have to show that the preimage of any subspace of $U$ is a subspace of $V$. My proof: Say $W$ is a subspace of ... , The proof is essentially correct, but you do have some unnecessary details. Removing redundant information, we can reduce it to the following:, To check that a subset \(U\) of \(V\) is a subspace, it suffices to check only a few of the conditions of a vector space. Lemma 4.3.2. Let \( U \subset V \) be a subset of a vector space \(V\) over \(F\). Then \(U\) is a subspace of \(V\) if and only if the following three conditions hold. additive identity: \( 0 \in U \);, Apr 8, 2018 · Let T: V →W T: V → W be a linear transformation from a vector space V V into a vector space W W. Prove that the range of T T is a subspace of W W. OK here is my attempt... If we let x x and y y be vectors in V V, then the transformation of these vectors will look like this... T(x) T ( x) and T(y) T ( y). If we let V V be a vector space in ... , A US navy ship intercepts missiles launched by Houthi rebels in Yemen. Two American bases in Syria come under fire. In Iraq, drones and rockets fired at US forces., Let V V be a vector space over F F and suppose that U U and W W are subspaces of V . V. Define U + W = \ { u + w | u \in U , w \in W \} . U +W = {u+w∣u ∈ U,w ∈ W }. Prove that: (a) U + W U + W is a subspace of V V . (b) U + W U +W is finite dimensional over F F if both U U and W W are. (c) U \cap W U ∩ W is a subspace of V V ., We begin this section with a definition. The collection of all linear combinations of a set of vectors {→u1, ⋯, →uk} in Rn is known as the span of these vectors and is written as span{→u1, ⋯, →uk}. Consider the following example. Describe the span of the vectors →u = [1 1 0]T and →v = [3 2 0]T ∈ R3., So I know for a subspace proof you need to prove that S is non-empty, closed under addition, and scalar Stack Exchange Network Stack Exchange network consists of 183 Q&A communities including Stack Overflow , the largest, most trusted online community for developers to learn, share their knowledge, and build their careers., and v2 ∈ / W1, v2 ∈ W2. Let v = v1 + v2. Then v = v1 + v2 ∈ / W1 ∪ W2. Why? Because if not, suppose v ∈ W1, then W1 is a subspace implies that v2 = v − v1 ∈ W1 — a contradiction (likewise if v ∈ W2). Hence v ∈ / W1 and v ∈ / W2. 3. Let W1 and W2 be …, Can lightning strike twice? Movie producers certainly think so, and every once in a while they prove they can make a sequel that’s even better than the original. It’s not easy to make a movie franchise better — usually, the odds are that me..., Let $U$ and $W$ be subspaces of $V$. Show that $U\cup W$ is a subspace of $V$ if and only if $U \subset W$ or $W \subset U$. I am not sure what I can do with the ..., Did you know that 40% of small businesses are uninsured? Additionally, most insured small businesses are inadequately protected because 75% of them are underinsured. Despite this low uptake, business insurance is proving to be necessary., through .0;0;0/ is a subspace of the full vector space R3. DEFINITION A subspace of a vector space is a set of vectors (including 0) that satisfies two requirements: If v and w are vectors in the subspace and c is any scalar, then (i) v Cw is in the subspace and (ii) cv is in the subspace., A subset W ⊆ V is said to be a subspace of V if a→x + b→y ∈ W whenever a, b ∈ R and →x, →y ∈ W. The span of a set of vectors as described in Definition 9.2.3 is an example of a subspace. The following fundamental result says that subspaces are subsets of a vector space which are themselves vector spaces., Advanced Math. Advanced Math questions and answers. 2. Let W be a subspace of a vector space V over a field F. For any v E V the set {v}+W :=v+W := {v + W:WEW} is call the coset of W containing v. (a) Prove that v+W is a subspace of V iff v EW. (b) Prove that vi+W = V2+W iff v1 – V2 E W. (c) Prove that S = {v+W :V EV}, the set of all cosets ..., T is a subspace of V. Also, the range of T is a subspace of W. Example 4. Let T : V !W be a linear transformation from a vector space V into a vector space W. Prove that the range of T is a subspace of W. [Hint: Typical elements of the range have the form T(x) and T(w) for some x;w 2V.] 1, Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site, Closed 3 years ago. If W₁ ⊆ W₂ ⊆ W₃......, where Wᵢ are the subspaces of a vector space V, and W = W₁ ∪ W₂ ∪...... Prove that W ≤ V. So I proved that: If W₁ and W₂ are two subspaces of V and W₁ ∪ W₂ ≤ V then W₁ ⊆ W₂ or W₂ ⊆ W₁., Exercise 3B.12 Suppose V is nite dimensional and that T2L(V;W). Prove that there exists a subspace Uof V such that U ullT= f0gand rangeT= fTuju2Ug. Proof. Proposition 2.34 says that if V is nite dimensional and Wis a subspace of V then we can nd a subspace Uof V for which V = W U. Proposition 3.14 says that nullT is a subspace of , This means P(F) = U W as desired. 15.) Prove or give a counterexample: if U 1; U 2; W are subspaces of V such that V = U 1 W and V = U 2 + W then U 1 = U 2. Solution: This is false. For an example, we take V = F2, U 1 = f(x;0) : x 2Fg, U 2 = f(z;z) : z 2Fgand W = f(0;y) : y 2Fg. From the textbook, these are all subspaces of V. We rst note that ..., Let W be a subspace of V and let u, v ∈ W. Then, for every α,β ∈ F, α u,β v ∈ W and hence α u + β v ∈ W. Now, we assume that α u + β v ∈ W, whenever α,β ∈ F and u, v ∈ W. To show, W is a subspace of V: DRAFT 1., $V$ and $ W $are two real vector spaces. $T: V \\rightarrow W$ is a linear transformation. What is the image of $T$ and how can I prove that it is a subspace of W?, 2. Let H and K be subspaces of a vector space V V. The intersection of H H and K K, , is the set of v v in V V that belong to both H H and K K. Show that the intersection of H H and K K is a subspace of V V. Give an example in R2 R 2 to show that the union of two subspaces is not, in general, a subspace. I know that in order to prove …, Next we give another important example of an invariant subspace. Lemma 3. Suppose that T : V !V is a linear transformation, and let x2V. Then W:= Span(fx;T(x);T2(x);:::g) is a T-invariant subspace. Moreover, if Zis any other T-invariant subspace that contains x, then WˆZ. Proof. First we show that W is T-invariant: let y2W. We have to show ..., So, in order to show that this is a member of the given set, you must prove $$(x_1 + x_2) + 2(y_1 + y_2) - (z_1 + z_2) = 0,$$ given the two assumptions above. There are no tricks to it; the proof of closure under $+$ should only be a couple of steps away.