Q7 of 268 Page 4

If A = 30^o, verify that :
sin 2A = 2 sin A cos A

Given: A =30^o

Now, LHS = sin 2(30^o)

⇒ sin 60^o

Now, RHS = 2 sin A cos A

⇒ 2 sin (30^o) cos (30^o)

∴ LHS = RHS

Hence Proved

If A=60^o and B = 30^o, verify that :

sin (A – B) = sin A cos B – cos A sin B

If A=60^o and B = 30^o, verify that :

tan (A – B) =

If A = 30^o, verify that :

cos 2A = 1-2 sin²A=2cos² A – 1

If θ = 30°, verify that :

sin 3θ = 3 sinθ – 4 sin³θ

If A = 30o, verify that :sin 2A = 2 sin A cos A