Question

if cosp+sinp=√2cosp show that cosp-sinp=√2sinp​

Answer 1

cosp+sinp=√2cosp

cosp=√2cosp-sinp ;-its  eqn 1

now,

cosp-sinp (substituting from eqn 1)

=√2cosp-sinp-sinp

=√2cosp

hence proved