Question

For a=30 degree, verify that cos 2A = cos^2A - sin^2A

Answer 1

Answer:

Step-by-step explanation:

Given      :- A = 30 degree

To prove :- cos 2A = cos^2A - sin^2A

Proof       :-

LHS

= cos 2*30

= cos 60

RHS

= cos^2 30 - sin^2 30

=  {$\sqrt{3}$/2}^2 - {1/2}^2

= 3/4 - 1/4

=2/4

=1/2

Since, LHS = RHS

Therefore, cos 2A = cos^2A - sin^2A

Hence proved

Hope this answer helps!