SOLUTION: show that sinθ = cosθ tanθ

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Question 207162: show that sinθ = cosθ tanθ
Found 2 solutions by jim_thompson5910, Theo:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
sinθ = cosθ tanθ .... Start with the given equation.


sinθ = cosθ (sinθ/cosθ) ... Rewrite tangent as sine over cosine


sinθ = 1*(sinθ/1) ... Cancel out the common terms.


sinθ = sinθ ... Simplify


So this verifies the identity.

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
sin(θ) = o%2Fh
cos(θ) = a%2Fh
tan(θ) = o%2Fa
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o = side opposite angle θ
a = side adjacent angle θ
h = hypotenuse of the right triangle.
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cos(θ) * tan(θ) = %28a%2Fh%29+%2A+%28o%2Fa%29 = %28%28a%2Ao%29%29%2F%28%28h%2Aa%29%29 = %28o%2Fh%29 because the a in the numerator cancels the a in the denominator.
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you are left with sin(θ) = %28o%2Fh%29 = cos(θ) * tan(θ)