Question

Find d(A.B) if the coordinates of point A are (1,8) and the coordinates of B are (-8,6).

A) -40
B) -22
C) 40
D) 22

Answer 1

The dot product d(A.B) of two vectors A and B is found by multiplying the corresponding components of the vectors and adding them up. For the given coordinates of point A and point B, d(A.B) = 40.

Step-by-step explanation:

To find the dot product d(A.B) of two vectors A and B, we multiply the corresponding components of the vectors and add them up.

The coordinates of point A are (1,8) and the coordinates of point B are (-8,6).

So, d(A.B) = (1)(-8) + (8)(6) = -8 + 48 = 40.

Therefore, the correct answer is C) 40.