Question

if theta = 30° verify cos2 theta = 2cos square theta -1​

Answer 1

Step-by-step explanation:

the answer is given to you

Answer 2

at first,

LHS

,cos 2×30°=60°= 1/2=2cos² theta -1

RHS,

1/2=2(✓3/2)²-1

=)1/2=2(3/4)-1

=)1/2=3/2-1. (2 and4 cutted so 2 has came ). =)1/2=3-2/2. (1 and2 multpilaid so 2 has came). =)1/2=1/2

HENCE PROVED