Introduction to Trigonometry Exercise 8.3

NCERT solutions for Maths Introduction to Trigonometry 

NCERT Solutions for Class 10 Maths Introduction to Trigonometry

1. Evaluate:

(i)

(ii)

(iii)

(iv)

Ans. (i) =

= = 1

(ii) =

= = 1

(iii)

=

= = 0

(iv)

=

= =0

2. Show that:

(i)

(ii)

Ans. (i)L.H.S.

=

=

= = 1 = R.H.S.

(ii) R.H.S.

=

= = 0 = R.H.S.

3. If where 2A is an acute angle, find the value of A.

Ans. Given:

A =

4. If prove that

Ans. Given:

A + B =

5. If where 4A is an acute angle, find the value of A.

Ans. Given:

A =

6. If A, B and C are interior angles of a ABC, then show that

Ans. Given: A, B and C are interior angles of a ABC.

A + B + C =

7. Express in terms of trigonometric ratios of angles between and

Ans.

=

=