# How to solve matrix as a function

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Josh on 15 Feb 2012
I know this is simple for some, but I need a hand. I am learning this as I go with no assistance.
If I have three known variables, or 3x1 matrix Theta. I know m=cosd(Theta), and n=sind(Theta), and I want to solve another matrix T for each of the three Theta, how would you code this?
Ex: T = [m^2,n^2,2mn; n^2,m^2,-2mn; m,n,m^2n^2]
How can I enter this in and get three separate T matrices as my output? Thanks!

Benjamin Schwabe on 15 Feb 2012
What does m^2 mean? It's a vecor, isn't it? Componentwise operation? Or is it a real vecor-vectormultiplication resulting in a single number?
Josh on 15 Feb 2012
m^2 is m squared, which will be a number in row1, column1. Likewise, n^2 is in row 1, column2, and so on. m=cosd(Theta). I am just trying to find the code where I can solve for all Thetas at once.

Walter Roberson on 15 Feb 2012

Andrei Bobrov on 15 Feb 2012
m = reshape(cosd(Theta),1,1,[])
mq = m.^2;
nq = 1 - mq;
n = sqrt(nq);
mn = 2*m.*n;
T = [mq, nq, mn; nq,mq,-mn; m,n,mq.*nq]