Q5 of 268 Page 5

If cos40^o = p, then write the value of sin 40^o in terms of p.

We know that

cos² θ + sin² θ = 1

⇒ cos² 40° + sin² 40° = 1

⇒ sin² 40° = 1 – cos² 40°

⇒ sin 40° = √(1 – cos² 40°)

And Given that cos 40° = p

⇒ sin 40° = √(1– p²)

If cos A = x, express sin A in terms of x

If x cos θ = 1 and y sin θ = 1 find the value of tan θ.

If sin 77° = x, then write the value of cos 77^o in terms of x.

If cos55° = x², then write the value of sin 55^o in terms of x.

If cos40o = p, then write the value of sin 40o in terms of p.