Integrals
\[\Large\rm \cos \theta\left[\frac{\sin \theta}{\cos \theta}+\frac{1}{\cos \theta}\right]\]Distribute the cos theta, should simplify things down quite a bit.
so \[\frac{ \cos(\theta)\sin(\theta) }{ \cos(\theta) }+\frac{ \cos(\theta) }{ \cos(\theta) }\]
The cos's cancel each other leaving sin(theta)+1 ?
Mmm yah looks good! Understand how to integrate those two terms?
I know how to do it without the trig functions, first time seeing them with integrals
When you take derivatives of your sine function it follows this pattern that I'm sure you're familiar with:\[\Large\rm \sin x\to \cos x\to -\sin x\to -\cos x\]And then it repeats that process. Errr lemme show just a few more on each side,\[\Large\rm -\cos x\to\sin x\to \cos x\to -\sin x\to -\cos x\to \sin x\] For integrating we just go backwards:\[\Large\rm -\cos x\leftarrow\sin x\leftarrow \cos x\leftarrow -\sin x\leftarrow -\cos x\leftarrow \sin x\]
So for sine, it just brings us back to uhhhh -cosine, yes?
right
so it would be x - cos(x)
Yah good job! With some type of +C on the end if you want.
right, yeah. Thanks!
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