Q5 of 268 Page 4

Prove the following :

We know that

Taking LHS =

Now, solving RHS = 2 sin 30° cos 30°

= LHS

Now, RHS

∴ LHS =RHS

Hence proved

Prove the following :

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

cos (A+B) = cos A cos B – sin A sin B

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

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