How to multiply a matrix by a column vector in Wolfram Alpha ...
math.stackexchange.com › questions › 3353841Sep 12, 2019 · Basically, you remove the inner sets of curly brackets, and you give it an explicit multiplication symbol, and you get a result: {{a,0,0,0},{0,b,0,0},{0,0,c,d},{0,0,e,0}}*{x/a,y/b,p,q} Alternately, you can add a second dummy column to your vector to force WA to think about the matrix the way you want it to, and then ignore the second column of the output.