Question

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Answer 1

We will have that the exact value for each function is:

21)

$\cot (180)=\text{not defined}$

22)

$\cos (-60)=\frac{1}{2}$

23)

$\sin (\frac{4\pi}{3})=-\frac{\sqrt[]{3}}{2}$

24)

$\sec (-\frac{7\pi}{4})=\sqrt[]{2}$