# NCERT Solutions For Class 10 Maths Chapter 8 Introduction to Trigonometry Ex 8.1

### Ex 8.1 Class 10 Maths Question 1.

In ∆ABC right angled at B, AB = 24 cm, BC = 7 cm. Determine:
(i) sin A, cos A
(ii) sin C, cos C

### Ex 8.1 Class 10 Maths Question 2.

In given figure, find tan P – cot R.

### Ex 8.1 Class 10 Maths Question 3.

If sin A , calculate cos A and tan A.

### Ex 8.1 Class 10 Maths Question 4.

Given 15 cot A = 8, find sin A and sec A.

### Ex 8.1 Class 10 Maths Question 5.

Given sec θ  calculate all other trigonometric ratios.

### Ex 8.1 Class 10 Maths Question 6.

If ∠A and ∠B are acute angles such that cos A = cos B, then show that ∠A = ∠B.

### Ex 8.1 Class 10 Maths Question 8.

If 3 cot A = 4, check whether = cos² A – sin² A or not.

### Ex 8.1 Class 10 Maths Question 9.

In triangle ABC, right angled at B, if tan A =  find the value of:
(i) sin A cos C + cos A sin C
(ii) cos A cos C – sin A sin C

### Ex 8.1 Class 10 Maths Question 10.

In ΔPQR, right-angled at Q, PR + QR = 25 cm and PQ = 5 cm. Determine the values of sin P, cos P and tan P.

### Ex 8.1 Class 10 Maths Question 11.

State whether the following statements are true or false. Justify your answer.
(i) The value of tan A is always less than 1.
(ii) sec A =for some value of angle A.
(iii) cos A is the abbreviation used for the cosecant of angle A.
(iv) cot A is the product of cot and A.
(v) sin θ =  for some angle.