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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Specialist Mathematics => Topic started by: Pking time 2 on March 08, 2014, 02:37:24 pm

Title: Matrices transformations
Post by: Pking time 2 on March 08, 2014, 02:37:24 pm

Transform the unit square with vertices A(0,0), B(1,0), C(1,1) and D(0,1) by the matrix E = [3 0 ] E is a 2 by 2 matrix. Please help I dont understand this question
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Title: Re: Matrices transformations
Post by: kinslayer on March 08, 2014, 06:27:16 pm

Turn each of the four points into 2-d vectors and then multiply them on the left by E.

You can use the fact that E is 3 times the identity matrix. The identity matrix is the "1" matrix (hence identity) which means that I*M = M*I = M for any M of the right size.

So the transformation is just dilation by a factor of three. The four vertices of the new square are A(0,0), B(3,0), C(3,3), D(0,3).