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Trigonometry help! How do I simplify this question... sums and differences of angles?
The following question is a fraction *
tan (x + y) + tan (x - y)
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1 - tan (x + y) tan (x - y)
1 Answer
Relevance
- FazLv 71 decade agoFavorite Answer
Let A=(x+y), B=(x-y), then the above expression is
[ tan(A) + tan(B) ] / [ 1 - tan(A)tan(B) ]
This is just the addiition formula for tan(A+B)
But from above, A+B = (x+y)+(x-y) = 2x
= tan(2x)
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