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Double angle formula help

Hello, in regards to the double angle formulas, I know that e.g. sin(2x)=2sin(x)cos(x), but let's say we want to know sin(5x); can you still use the double angle formula for this?

So would sin(5x)=2sin(2.5x)cos(2.5x)?

Furthermore, for the small angle approximations (e.g. tanx=x when x is very small), if we are given tan3x for a very small value of x, can we just say that tan3x=3x when x is very small?

thanks

Reply 1

RDKGames

Study Forum Helper

Original post by Bertybassett

Yeah.

Furthermore, for the small angle approximations (e.g. tanx=x when x is very small), if we are given tan3x for a very small value of x, can we just say that tan3x=3x when x is very small?

thanks

Yeah.