Question

The value of $\sin ({45}^{\circ }+\theta )-\cos ({45}^{\circ }-\theta )$ is

• A. $1$
• B. $0$
• C. $2\cos \theta$
• D. $2\sin \theta$

Answer 1

The correct option is B $0$

$\sin ({45}^{\circ }+\theta )-\cos ({45}^{\circ }-\theta )$
$=\sin (90-({45}^{\circ }-\theta \left)\right)-\cos ({45}^{\circ }-\theta )$
$=\cos ({45}^{\circ }-\theta )-\cos ({45}^{\circ }-\theta )$
$=0$