Matrix Times Vector, Checked Two Ways — easy Matrix Multiplication problem | Incognition
Matrix Times Vector, Checked Two Ways
Matrix MultiplicationEasy+10 XP+10
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.
Both routes must land on the same vector.
Which vector is Av?
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