If tan 2A = cot (A – 18°), where 2A is an acute angle, find the value of A

Solution:

We will be using the trigonometric ratios of complementary angles to solve the given question.

tan (90° - θ) = cot θ

Given that:

tan 2A = cot (A - 18°) ….(i)

But tan 2A = cot (90° - 2A)

By substituting this in equation (i) we get:

cot (90° - 2A) = cot (A - 18°)

90° - 2A = A - 18°

3A = 108°

A = 108°/3

A = 36°

☛ Check: NCERT Solutions Class 10 Maths Chapter 8

Video Solution:

If tan 2A = cot (A – 18°), where 2A is an acute angle, find the value of A

Maths NCERT Solutions Class 10  Chapter 8 Exercise 8.3 Question 3

Summary:

If tan 2A = cot (A - 18°), where 2A is an acute angle, then the value of A is 36°.

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