$\frac{r}{x}$  

 $\frac{x}{r}$  

 $\frac{y}{r}$  

 $\frac{r}{y}$  

 $\frac{x}{y}$  

$270^{\degree}<\theta<360^{\degree}$

$180^{\degree}<\theta<270^{\degree}$

$90^{\degree}<\theta<180^{\degree}$

$0^{\degree}<\theta<90^{\degree}$

 $\frac{1}{\sqrt{3}}$  

 $-\sqrt{3}$  

1

 $3\sqrt{3}$  

 $\frac{\sqrt{3}}{3}$  

 $\theta=30^{\degree}\ ,\ 120^{\degree}$  

 $\theta=60^{\degree},\ 120^{\degree}$  

 $\theta=60^{\degree}\ ,\ 300^{\degree}$  

 $\theta=120^{\degree}\ ,\ 240^{\degree}$  

 $\theta=120^{\degree}\ ,\ 300^{\degree}$  

$\cos^2\theta=1-\sin^2\theta$

$1=\operatorname{cosec}^2\theta-\cot^2\theta$

$\tan^2\theta=\sec^2\theta-1$

$\operatorname{cosec}^2\theta=\cot^2\theta-1$

 $\theta\ =\ 14.5^{\degree}\ ,\ 50^{\degree}\ ,\ 175.5^{\degree}$  

 $\theta=60^{\degree}\ ,\ 90^{\degree}\ ,\ 165.5^{\degree}$  

 $\theta=14.5^{\degree}\ ,\ 90^{\degree}\ ,\ 165.5^{\degree}\ ,\ 270^{\degree}$  

 $\theta=60^{\degree},\ 90^{\degree},\ 120^{\degree}$  

 $\theta=14.5^{\degree}\ ,\ 90^{\degree}\ ,\ 165.5^{\degree}$  

 $\cos7\theta$  

 $\cos4\theta$  

 $\sin7\theta$  

 $\cos3\theta$  

 $\cos\theta$  

 $\frac{24}{7}$  

 $\frac{7}{25}$  

 $\frac{6}{4}$  

 $\frac{9}{16}$  

 $\frac{24}{25}$  

 $-\frac{2}{\sqrt{3}}$  

 $\sqrt{3}$  

 $3$  

 $\frac{1}{\sqrt{3}}$  

 $-\frac{1}{3}$  

 $\theta=36.9^{\degree}\ ,\ 143.1^{\degree}$  

 $\theta=143.1^{\degree},\ 216.9^{\degree}$  

 $\theta=216.9^{\degree}\ ,\ 323.1^{\degree}$  

 $\theta=143.1^{\degree}\ ,\ 323.1^{\degree}$  

 $\theta=36.9^{\degree}\ ,\ 216.9^{\degree}$  

$\cos\theta=\cos^2\ \frac{\theta}{2}-\sin^2\ \frac{\theta}{2}$

$\sin\theta=2\sin\ \frac{\theta}{2}\cos\ \frac{\theta}{2}$

$\tan\theta=\frac{2\tan\ \frac{\theta}{2}}{1-\tan^2\ \frac{\theta}{2}}$

$\cos\theta=2\cos^2\ \frac{\theta}{2}-1$

$\cos\theta=1+2\sin^2\ \frac{\theta}{2}$