If cos=(-5/13), $tan theta > 0$ , what is $sin theta$ ?

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Answer 1 · 2016-06-27T04:52:42

$sintheta=-12/13$

If $costheta<0$ and $tantheta>0$

then $theta$ is in the third quadrant, where $sintheta<0$

$sintheta=-sqrt(1-cos^2theta)$

$sintheta=-sqrt(1-(5/13)^2)$

$sintheta=-sqrt(1-25/169)$

$sintheta=-sqrt(144/169)$

$sintheta=-12/13$

If cos=(-5/13), tan theta > 0tan theta > 0, what is sin thetasin theta?