Matrix Times Vector, Checked Two Ways — easy Matrix Multiplication problem | Incognition
Matrix Times Vector, Checked Two Ways
10 pts · 10 coins
Matrix MultiplicationEasy
Matrix Times Vector, Checked Two Ways
A=302−2411−15,v=2−13
There are two equivalent ways to read the product Av:
Row view: entry i of the answer is the dot product of row i of A with v.
Column view: the whole answer is v1c1+v2c2+v3c3, where ck is column k of A — a weighted blend of A's columns, with the weights taken from v in order.