Question

Given u(-8,-9) and v(3,7), what is -3(u•v)?

Answer 1

First, we need to find the dot product of u and v, denoted by u•v. The dot product of two vectors u = (u1, u2) and v = (v1, v2) is given by:

u•v = u1v1 + u2v2

So, for u(-8,-9) and v(3,7), we have:

u•v = (-8)(3) + (-9)(7) = -24 - 63 = -87

Next, we can multiply -3 by the dot product of u and v:

-3(u•v) = -3(-87) = 261

Therefore, -3(u•v) is equal to 261.