Question

2ncos 20=sin 40+ncos40 the value of 1÷n² is​

Answer 1

Step-by-step explanation:

Let A= sqrt(3).cos(20)- sin(20)

Replace tan(60)= sqrt(3) in above expression

A= sin(60). cos(20)/cos(60)- sin(20)

Or A.cos(60)= sin(60).cos(20)- sin(20).cos(60)= sin (60-20)= sin(40)

So A= 2.sin(40)= sqrt(3).cos(20)- sin(20)

Or sin(20)+2.sin(40)= sqrt(3).cos(20)