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Let B {bı, b2} and C = {c1, c2} be bases for R^2 where bı [-1;8]. b2 [1;-5], c1 = [1;4]. Find the change-of-coordinates matrix from B to C and the change-of-coordinates matrix from C to B.

User Ori Folger
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Answer:

Let B {bı, b2} and C = {c1, c2} be bases for R^2 where bı [-1;8]. b2 [1;-5], c1 = [1;4]. Find the change-of-coordinates matrix from B to C and the change-of-coordinates matrix from C to B.

In the given problem, we have the bases B and C as follows:

B = {b1, b2} where b1 = [-1;8] and b2 = [1;-5]

C = {c1, c2} where c1 = [1;4] and c2 = [0;1]

We need to find the change-of-coordinates matrix from B to C and from C to B.

To find the change-of-coordinates matrix from B to C, we need to express the basis vectors of B in terms of the basis vectors of C. We can do this by solving the following equations:

b1 = x1c1 + y1c2

b2 = x2c1 + y2c2

where x1 , y1, x2, and y2 are the coefficients we want to find.

Substituting the given values, we get:

[-1;8] = x1*[1;4] + y1*[0;1]

[1;-5] = x2*[1;4] + y2*[0;1]

Solving these equations, we get:

x1 = -17/4, y1 = 1/4, x2 = 9/4, and y2 = -1/4

Therefore, the change-of-coordinates matrix from B to C is:

[-17/4 9/4]

[ 1/4 -1/4]

To find the change-of-coordinates matrix from C to B, we need to express the basis vectors of C in terms of the basis vectors of B. We can do this by solving the following equations:

c1 = a1b1 + a2b2

c2 = b1b1 + b2b2

where a1 , a2, b1, and b2 are the coefficients we want to find.

Substituting the given values and solving these equations, we get:

a1 = 4/17, a2 = -1/17, b1 = -1/17, and b2 = -5/17

Therefore, the change-of-coordinates matrix from C to B is:

[ 4/17 -1/17]

[-1/17 -5/17]

I hope this helps!

Explanation:

User PhML
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