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(1+sint)/(cost)-(cost)/(1-sint)

User Gavdotnet
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1 Answer

10 votes


(1+\sin(t))/(\cos(t)) - (\cos(t))/(1-\sin(t))

Multiply through the second term by
1+\sin(t) :


(1+\sin(t))/(\cos(t)) - (\cos(t))/(1-\sin(t))\cdot(1+\sin(t))/(1+\sin(t))


(1+\sin(t))/(\cos(t)) - (\cos(t)(1+\sin(t)))/(1-\sin^2(t))

Recall that
\cos^2(x)+\sin^2(x)=1 for all x :


(1+\sin(t))/(\cos(t)) - (\cos(t)(1+\sin(t)))/(\cos^2(t))

If
\cos(t)\\eq0, we can cancel a factor of it in the second fraction.


(1+\sin(t))/(\cos(t)) - (1+\sin(t))/(\cos(t))

and this simplifies to


((1+\sin(t))-(1+\sin(t)))/(\cos(t)) = \boxed{0}

User Slashdottir
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