Question

if x=rcosAcosB, y=rcoaAsinB and z=rsinA then prove that x^2 +y^2 +z^2 =r^2

Answer 1

Answer:

r^

Step-by-step explanation:

r^2(cosx^2.cosy^2+cosx^2.siny^2+sinx^2)

r^2[cosx^2(cosy^2+siny^2)+sinx^2]

r^2[cosx^2(1)+sinx^2]

r^2×1. (sinx^2+cosx^2)=1

hence r^2=x^2+y^2+z^2