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Highlights Math 304 Linear Algebra From last time: I Harold P. Boas boas@tamu.edu linear transformations Today: I matrix representations of linear transformations June 14, 2006 Example Example continued A certain linear operator L on R 2 has the following action: input: Composing the preceding operator with a reflection and a rotation produces a new transformation T that takes Math 304 Math 304 into ht a M Determine L. 1 1 0 1 Since L = and L = , the transformation L 0 0 1 1 1 1 is represented by multiplication by the matrix whose 0 1 columns are the images under L of the standard basis vectors. 4 0 3 Math 304 output: Find a matrix that represents the new transformation T . Example modified for a nonstandard basis The previous cases represented transformations with respect to the standard basis. 1 1 Consider a nonstandard basis u1 = and u2 = . 1 −1 I What matrix A transforms the u-coordinates of a vector x into the standard coordinates of the image T (x)? I What matrix B transforms the u-coordinates of a vector x into the u-coordinates of the image T (x)? I What matrix C transforms the u-coordinates of a vector x 2 into the v-coordinates of the image T (x), where v1 = 1 3 and v2 = ? 2