Question

If 2sin theta minus 1=1.prove that sin30 = 3sin theta minus 4 sin cube theta

Answer 1

Answer:

2sin theta-1=1

2sin theta =1+1

2sin theta=2

sin theta=2/2

sin theta=1

Now,

sin 30=

3 sin theta -4 sin3 theta

sin30=1/2

So,

To prove is 1/2,

Hence,

3 sin theta-4 sin3 theta

3*1-4(sin theta) 3

3-4 (1)3

3-4*1

3-4

-1

But answer is coming -1 so your question is wrong