Question 1188278
If tan(x) + tan(y) = 4 and cot(x) + cot(y) = 5, find the value of tan(x+y)
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Sub r for tan(x) and s for tan(y)
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r + s = 4
{{{1/r + 1/s = 5}}}
{{{s + r = 5rs}}}
4 = 5rs
4 = tan(x)*tan(y)
tan(x) + tan(y) = tan(x)*tan(y)
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