Neha Tyagi and Amit Rastogi Solutions for Chapter: Introduction to Trigonometry and its Applications, Exercise 1: Exercise

If $△ABC$ is right-angled at $C,$ then the value of $\cos \left(A+B\right)$is

If $\sin A+{\sin }^2 A=1,$then the value of $\left({\cos }^{2}A+{\cos }^4 A\right)$ is

If $\sin \alpha =\frac{1}{2}$ and $\cos \beta =\frac{1}{2},$ then the value of $\left(\alpha +\beta \right)$ is

The value of the expression $\left(\frac{{\sin }^2 22°+{\sin }^2 68°}{{\cos }^2 22°+{\cos }^2 68°}+{\sin }^{2}63°+\cos 63° \sin 27°\right)$ is

If $4 \tan \theta =3,$then $\left(\frac{4 \sin \theta - \cos \theta }{4 \sin \theta + \cos \theta }\right)$ is equal to

If $\sin \theta -\cos \theta =0$, then the value of $\left({\sin }^4\theta +{\cos }^4\theta \right)$ is

$\sin \left(45°+\theta \right)-\cos \left(45°-\theta \right)$ is equal to 

If a pole $6 \mathrm{m}$ high casts a shadow $2\sqrt{3}$ m long  on the ground, then the Sun's elevation is