Integrating Factor/Initial Value Problem with Trig

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The problem is as follows:

Solve the initial value problem $$9(\sin(t)\frac{dy}{dt} + \cos(t)y) = (\cos(t))(\sin(t))^3, $$ for $ 0 < t < \pi$ and $y(\pi/2) = 9$.


So far I have this by dividing by $9\sin(t)$: $$\frac{dy}{dx} + cot(t)y = \frac{\cot(t)\sin^2(t)}{9}, $$

Then used the integrating factor of $e^{\cot(t)}$ in order to get: $$\frac{d}{dt}(e^{\cot(t)}y) = e^{\cot(t)} \frac{\cot(t)\sin^2(t)}{9}, $$ I do not know how to proceed from here as the integration itself is complex and my current process does not seem to be right.

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First, when you divide through, the coefficient on $y$ is also divided by 9, and the rhs should have $\cos$ not $\cot$.

Second, the integrating factor is $e^{\int \cot t/9 \; dt}$, which, as Moo says, turns out to be $\sqrt[9]{\sin t}$. This makes the "hard" integral on the rhs into a fairly easy $u$-sub.