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    • Thread Starter

    Hey again guys,

    I need to solve sin(x+30) = 2cos(x+45)

    I'm thinking that to simplify this, I should use compound angle formula on the sin function and the cos function. Is this the right way to go about solving it, or should I be using R,A formula. And why?


    You can use either or because both can independently be derived from the other.

    Given that, I would use compound angle because I find evaluating sine and cosine (even if it's both) easier than evaluating tangent, and you don't have to go around finding the coefficients a and b.
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