SOLUTION: This is a trignometry problem on proving identities I can use:double-angle,sum and difference,phythagorean identities, and ratios Question: Prove: sin(3<font face = "symbol">q

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Question 529275: This is a trignometry problem on proving identities
I can use:double-angle,sum and difference,phythagorean identities, and ratios
Question:
Prove: sin(3q) = 3sin(q) - 4sin³(q)



Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
sin(3q)
sin(2q + q)
sin(2q)cos(q) + cos(2q)sin(q)
[2sin(q)cos(q)]cos(q) + [cos²(q)-sin²(q)]sin(q)
2sin(q)cos²(q) + [1-sin²(q)-sin²(q)]sin(q)
2sin(q)cos²(q) + [1-2sin²(q)]sin(q)
2sin(q)[1-sin²(q)] + sin(q) - 2sin³(q)
2sin(q) - 2sin³(q) + sin(q) - 2sin³(q)
3sin(q) - 4sin³(q)