练习

Matrix-Vector Compatibility

Consider the matrix \(A\) created by the R code:

A = matrix(c(1, 2, 3, -1, 0, 3), nrow = 2, ncol = 3, byrow = TRUE)

Which of the following vectors \(\vec{b}\) can be multiplied by \(A\) to create \(A\vec{b}\)?

50 XP

b = c(1, 1, -1)

b = c(-2, 2)

b = c(2, -1, 3, 4, 7)

b = c(-1, 2, 1, 3)