# Find the value of the trigonometric function $\cot(\large\frac{-15\pi}{4})$

$\begin{array}{1 1}(A)\;1&(B)\;-1\\(C)\;\sqrt 3&(D)\;0\end{array}$

We know that value of $\cot x$ repeats after an interval of $2\pi$ or $360^{\large\circ}$
$\cot (\large\frac{-15\pi}{4})=$$\cot (-4\pi+\large\frac{\pi}{4}) \Rightarrow \cot \large\frac{\pi}{4}$$=1$
Hence (A) is the correct answer.