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$$\text{If}\quad \frac{\sin A}{\sin B}=\frac{\sqrt{3}}{2} \quad\text{and}\quad \frac{\cos A}{\cos B}=\frac{\sqrt{5}}{2}\,, \quad\text{then}\quad \tan A+\tan B = \text{???}$$ Here, $0<A,B<\frac\pi2$.

I tried many times but I am getting no result. Please help with some hint.

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  • $\begingroup$ The question is not quite clear. Are you trying to find values for $A$ and $B$ for which the two equations hold? $\endgroup$
    – stewbasic
    Commented Aug 19, 2016 at 2:11
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    $\begingroup$ What is your question? Can you review what you posted? $\endgroup$
    – DeepSea
    Commented Aug 19, 2016 at 2:11
  • $\begingroup$ @deepsea I did some edit to the question. $\endgroup$
    – danny
    Commented Aug 19, 2016 at 2:45
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    $\begingroup$ He is only asking for a hint, not for a full solution. No need to close... $\endgroup$
    – imranfat
    Commented Aug 19, 2016 at 2:52
  • $\begingroup$ Hint: square up and add those two: $sin A = \sqrt{3} / 2 \;sin B,\; cos A = \sqrt{5} / 2 \;cos B$. $\endgroup$
    – dxiv
    Commented Aug 19, 2016 at 2:55

1 Answer 1

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hint: $1 = \dfrac{3\sin^2B+5\cos^2B}{4}=\dfrac{5-2\sin^2B}{4}\implies \sin B = \dfrac{1}{\sqrt{2}}$. Can you continue to the finish line?

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