Question

Find the value of the following expressions:
$\frac{\cos ({360}^{\circ }-A)}{\sin ({270}^{\circ }+A)}+\frac{\cot ({90}^{\circ }+A)}{\tan ({180}^{\circ }-A)}+\frac{\sin ({90}^{\circ }-A)}{\sin ({90}^{\circ }+A)}$

Answer 1

$\frac{\cos ({360}^{\circ }-A)}{\sin ({270}^{\circ }+A)}+\frac{\cot ({90}^{\circ }+A)}{\tan ({180}^{\circ }-A)}+\frac{\sin ({90}^{\circ }-A)}{\sin ({90}^{\circ }+A)}$

$\frac{\cos A}{-\cos A}+\frac{\tan A}{-\tan A}+\frac{\cos A}{\cos A}$

$=-1+1+1=1$