Question

1) cos$ sin(90-$) + sin$ cos(90-$) = 1​

Answer 1

Step-by-step explanation:

Cos $ = sin (90-$)

sin $=cos (90- $)

= cos$*cos$+sin$*sin$

=

${ \cos}^{2} a + {sin}^{2} a = 1$

= cos square $ + sin square $

=1

lhs = rhs

hence proved