Question

plz prove it as fast as possible...​

Answer 1

Answer:

Considering the LHS:

sin 70 can be written as cos 20 by identity sin A = cos(90-A)

and

cos theta can be written as sin(90-theta)

thus substituting appropriate values we get 1+1=2

Hence Proved

Quad Erat Demonstrandum

Answer 2

Answer:

here's your answer..it's very easy..just use identity