# Class 10 – Introduction to Trigonometry – Previous years Questions

Previous Years Questions Important Questions**Introduction to Trigonometry – Previous years Questions**

- The value of
*θ*for which cos(10° +*θ*) = sin 30° , is- 50°
- 40°
- 80°
- 20°
**[CBSE 2020] [1 Mark]**

- The value of
*θ*for which sin (44° +*θ*) = cos 30° , is- 46°
- 60°
- 16°
- 90°
**[CBSE 2020] [1 Mark]**

- If tan A = 1, then 2 sin A cos A = ________.
**[CBSE 2020] [1 Mark]** - What is the value of (cos
^{2}67° – sin^{2}23°)?**[CBSE 2018] [1 Mark]** - In figure, PS = 3 cm, QS = 4 cm, ∠PRQ =
*θ*, ∠PSQ = 90° , PQ**⊥**RQ and RQ = 9 cm. Evaluate tan*θ*.**[CBSE 2019] [1 Mark]** - If tan α = 5/12, find the value of sec α.
**[CBSE 2019] [1 Mark]** - Evaluate:

**[CBSE 2020] [2 Marks]** - Evaluate:

**[CBSE 2020] [2 Marks]** - If 4 tan
*θ*= 3, evaluate

.**[CBSE 2018] [3 Marks]** - If tan 2A = cot(A -18°), where 2A is an acute angle, find the value of A.
**[CBSE 2018] [3 Marks]** - A, B and C are interior angles of a triangle ABC. Show that
- If ∠A = 90°, then find the value of tan.
**[CBSE 2019] [3 Marks]**

- If ∠A = 90°, then find the value of tan.
- If tan (A+B) = 1 and tan (A-B) = 1/√3, 0° < A+B < 90°, A>B, then find the value of A and B.
**[CBSE 2019] [3 Marks]** - Prove that :

**[CBSE 2020] [3 Marks]** - Prove that

.**[CBSE 2018] [4 Marks]** - If 1+sin
^{2}*θ*= 3sin*θ*cos*θ*, then prove that tan*θ*= 1 or tan*θ*= 1/2.**[CBSE 2019] [4 Marks]** - Prove the following:

**[CBSE 2019] [4 Marks]** - Prove that:

**[CBSE 2019] [4 Marks]**

## Comments

## Sudhanshu Raj

sir answer to likh dejiye