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**adkinsjr** ** 2. Let f(x)=x-2cosx, where x is greater than or equal to 0, but less than or equal to 2 pie.**

**a. On what intervals is f increasing or decreasing?**

**b. On what intervals is f concave upward or concave downward?**

Ok, so we want examine the derivative of the function $\displaystyle f(x)=x-2cosx$ on the interval $\displaystyle [0,2\pi]$. If $\displaystyle f'(x)>0$, then the function is increasing. If $\displaystyle f'(x)<0$, then the function is decreasing.

If $\displaystyle f''(x)>0$, then the function is concave upward.