Question

if sin a = 1÷2 hen find the velue of 3 sin a-4sin3

Answer 1

sin a = 1/ 2___________ Eq no 1.

3 sin a = 3/2.

4 sin 3= 4 sin a → a = 3

4 sin 3= 4 sin3.

put value of a= 3 in Eq no 1 , we get

sin 3 = 1/2

3 sin a - 4 sin 3= 3/2 - 4 /2
=( 3-4)/ 2 [ Taken LCM ]
= -1/2.