Answer:
A=Point (5,7) when represented in terms of vector = 5 i + 7 j
B=Point (-8,2) ,when represented in terms of vector = -8 i + 2 j
Dot Product of two vectors = A.B
Keep in mind
1.⇒i.i=1, j.j=1,i.j=j.i=0
2.Dot product of two vectors is Scalar Quantity.
So,→ A. B= (5 i + 7 j) . (-8 i +2 j)
= 5 × -8 +7 × 2
= -40 +14
= -26
