Q5 of 164 Page 41

If 5cos θ – 12 sin θ = 0, find

5cosθ –12sinθ = 0

⇒ 5cosθ = 12sinθ

⇒ tanθ = 5/12

Let the third side be p,

By Pythagoras theorem,

⇒ 5² + 12² = P²

⇒ 25 + 144 = p²

⇒ p² = 169

⇒ p = 13

Therefore, the other angles are:

sin θ =

cos θ =

Putting values in the function as:

⇒

In ΔABC, right angled at B, AB = 10 and AC = 26. Find the six trigonometric ratios of the angles A and C.

If 5cos θ – 12 sin θ = 0, find

If 29cosθ = 20 find sec² θ – tan² θ.