Answer
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Work Step by Step
The basic cosine curve in the form of $y=cos(x)$ is periodic and oscillates within $[-1,1]$ around the x-axis with a period of $2\pi$. At $x=0$, $y=1$ is a maximum and at $x=\pi$, $y=-1$ is a minimum. In the period of $[0,2\pi]$, it crosses the x-axis at $x=\frac{\pi}{2}$ and $x=\frac{3\pi}{2}$.
