Question

4 (sin (pi/2+x)+cos (pi+x)+sin (pi-x))/sin x

Answer 1

$\frac{4(sin(\pi/2 +x)+cos(pi+x)+sin(\pi -x))}{sinx} = \frac{4(cosx-cosx+sinx)}{sinx} =\frac{4sinx}{sinx} =4$