Question

prove that sin 18 = root5-1/4

Answer 1

Answer:

to prove sin 18=root5-1/4

first step :sin90=sin 5x18

you know sin 90 is 1

sin 90 is equal to sin(18+72)

sin(18+72) is in the form of sin(a+b)

apply the formula and then continue to simplify in such manner and after 4 to 5 such step you reach to the final solution