I have to find sinA from the equation where no value for sin function is given.Like an equation in variable sinA
–
Naren Ezhil
·
2 years, 1 month ago

Log in to reply

@Naren Ezhil
–
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 \(\sin^2(A) + \cos^2(A) = 1 \).
–
Pi Han Goh
·
2 years, 1 month ago

Log in to reply

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 :

\(\sin (3A) = 3\sin (A) - 4\sin^{3} (A)\)
–
Azhaghu Roopesh M
·
2 years, 1 month ago

## Comments

Sort by:

TopNewestI have to find sinA from the equation where no value for sin function is given.Like an equation in variable sinA – Naren Ezhil · 2 years, 1 month ago

Log in to reply

– Pi Han Goh · 2 years, 1 month ago

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 \(\sin^2(A) + \cos^2(A) = 1 \).Log in to reply

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 :

\(\sin (3A) = 3\sin (A) - 4\sin^{3} (A)\) – Azhaghu Roopesh M · 2 years, 1 month ago

Log in to reply

– Krishna Sharma · 2 years, 1 month ago

How was your bits?Log in to reply

– Azhaghu Roopesh M · 2 years, 1 month ago

I got 341 .Log in to reply