# Samacheer Kalvi 9th Maths Solutions Chapter 6 Trigonometry Additional Questions

## Tamilnadu Samacheer Kalvi 9th Maths Solutions Chapter 6 Trigonometry Additional Questions

Exercise 6.1

Question 1.
Find the six trigonometric ratios of the angle 6 using the diagram
Solution:

Question 2.
If 3 cot θ = 1, then find the value of $$\frac{3 \cos \theta-4 \sin \theta}{5 \sin \theta+4 \cos \theta}$$
Solution:

Question 3.

Solution:

Hence proved

Question 4.
If 3 (tan θ) + 4 (sec θ × sin θ) = 24. Then find all the trigonometric ratios of the angle θ.
Solution:

Question 5.
From the given figure, find all the trigonometric ratios of angle θ.
Solution:

Exercise 6.2

Question 1.
Find the value of sin 3x. sin 6x. sin 9x when x = 10°
Solution:

Question 2.
Find the value of cot 15°. cot 30°. cot 45°. cot 60°. cot 75°
Solution:
cot (90° – 75) cot (90° – 60°) cot 45° cot 60° cot 75°
= tan 75° tan 60° (1) cot 60° cot 75° = 1

Exercise 6.3

Question 3.
Find the value of cos 19° 59′ + tan 12° 12′ + sin 49° 20′.
Solution:
cos 19° 59′ + tan 12° 12′ + sin 49° 20′ = 0

Question 4.
Given that sin α = $$\frac{1}{\sqrt{2}}$$ and tan β = $$\sqrt{3}$$ . Find the value of α + β.
Solution:

Question 5.
Find the value of $$\frac{\cos 63^{\circ} 20^{\prime}}{\sin 26^{\circ} 40^{\prime}}$$
Solution: