Question : Find the exact value of $\cos 120°$.

Option 1: 1

Option 2: 0

Option 3: – 0.5

Option 4: 0.5

Question : Find the value of $\cos 47^\circ \sec 133^\circ + \sin 44^\circ \text{cosec}\; 136^\circ $.

Option 1: $\frac{1}{2}$

Option 2: $1$

Option 3: $0$

Option 4: $–1$

Question : If $0\leq\theta\leq 90^{\circ}$ and $4\cos^{2}\theta-4\sqrt{3}\cos\theta+3=0$, then the value of $\theta$ is:

Option 1: $30^{\circ}$

Option 2: $45^{\circ}$

Option 3: $90^{\circ}$

Option 4: $60^{\circ}$

Question : What is the value of $5 \sqrt{3} \cos 60^{\circ} \tan 30^{\circ}-3 \cos 0^{\circ}+3 \cos ^2 45^{\circ}+2 \sin ^2 60^{\circ}$?

Option 1: $2\sqrt{3}$

Option 2: $2.5$

Option 3: $3.5$

Option 4: $3\sqrt{2}$

Question : Find the value of $\frac{\cos^2 15^{\circ}-\sin^2 15^{\circ}}{\cos^2 145^{\circ}+\sin^2 145^{\circ}}$.

Option 1: $\frac{1}{\sqrt{3}}$

Option 2: $\frac{1}{1-\sqrt{3}}$

Option 3: $\frac{\sqrt{3}}{2}$

Option 4: $\frac{2}{\sqrt{3}}$