Question

If a+b = a - b prove that the angle between a and b is 90°.​

Answer 1

Answer:

A+b=a-b

Explanation:

(a+b)'2=a^2+b^2+2abcos(angle)

Angle=90

(a+b) ^2=a^2+b^2

Cos(90)=0

a^2+b^2=(a-b)^2

(a+b)^2=(a-b)^2

Square root on both sides

A+b=a-b