Hint: State \(\sin(3A) = \sin(2A + A) = \sin(2A) \cos(A) + \cos(A) \sin(2A) \). Use the double angle formula for \(\cos(2A) \) and \(\sin(2A) \) and apply the fundamental identity \(\sin^2(A) + \cos^2(A) = 1 \).

What's the big difference if you write \(\sin (3A)\) in terms of \(\sin (A)\) or vice-versa ? All you will be needing is a relation between the two , and it is :

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TopNewestI have to find sinA from the equation where no value for sin function is given.Like an equation in variable sinA

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Hint: State \(\sin(3A) = \sin(2A + A) = \sin(2A) \cos(A) + \cos(A) \sin(2A) \). Use the double angle formula for \(\cos(2A) \) and \(\sin(2A) \) and apply the fundamental identity \(\sin^2(A) + \cos^2(A) = 1 \).

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What's the big difference if you write \(\sin (3A)\) in terms of \(\sin (A)\) or vice-versa ? All you will be needing is a relation between the two , and it is :

\(\sin (3A) = 3\sin (A) - 4\sin^{3} (A)\)

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How was your bits?

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I got 341 .

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