Question

The value of sin θ cos(90° – θ) + cos θ sin (90° – θ) is ___________.

Answer 1

$$\begin{gathered} \sin \theta \cos \left(90°-\theta \right)+\cos \theta \sin \left(90°-\theta \right) \\ =\sin \theta \times \sin \theta +\cos \theta \times \cos \theta \left[\cos \left(90°-\theta \right)=\sin \theta \mathrm{and}\sin \left(90°-\theta \right)=\cos \theta \right] \\ ={\sin }^2\theta +{\cos }^2\theta \\ =1 \end{gathered}$$

The value of sin θ cos(90° – θ) + cos θ sin (90° – θ) is _____1_____.