So I thought I understood how to do these problems until I got to this one. Could someone explain it to me please.

11) Find the points and state whether it is increasing or decreasing. sint 0 less than or equal to t less than or equal to 2pi

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- Oct 23rd 2012, 07:25 PM #1

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## Monotonicit problem Help please

So I thought I understood how to do these problems until I got to this one. Could someone explain it to me please.

11) Find the points and state whether it is increasing or decreasing. sint 0 less than or equal to t less than or equal to 2pi

- Oct 23rd 2012, 08:06 PM #2

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- Oct 23rd 2012, 08:11 PM #3

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- Oct 24th 2012, 08:24 AM #4

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## Re: Monotonicit problem Help please

I've never heard of the monotonicity theorem before, but I probably know it by another name (or perhaps by no name at all).

The derivative of $\displaystyle \sin{t}$ is $\displaystyle \cos{t}$ which is positive for $\displaystyle 0<t<\frac{\pi}{2}$ and $\displaystyle \frac{3\pi}{2}<t<2\pi$ and negative for $\displaystyle \frac{\pi}{2}<t<\frac{3\pi}{2}$.

- Hollywood