SOLUTION: proving compound angle formula a) tan(x+45)-tan(x-45)= 4tanx/1-tan^2x b) sin(x-30)-cos(x+60)=square root 3sinx-cos x plz help me am stuck thx lots

Question 1119399: proving compound angle formula
a) tan(x+45)-tan(x-45)= 4tanx/1-tan^2x

b) sin(x-30)-cos(x+60)=square root 3sinx-cos x
plz help me am stuck thx lots
Found 2 solutions by Edwin McCravy, AnlytcPhil:
Answer by Edwin McCravy(20060) (Show Source): You can put this solution on YOUR website!

That's not true, for if you substitute x = 100�, you get 45.71229319 = -3.585054968, so you must have copied it wrong. But the second one is true: Work with left side only: Edwin

Answer by AnlytcPhil(1807) (Show Source): You can put this solution on YOUR website!

I have discovered what your copying error in the first one must have been.��The sign between the terms in the numerator of the left side should have been +, not -. Work with left side only: ---------------------------------------------------------- Work with left side only: Edwin (aka AnlytcPhil)

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