Q3 of 268 Page 5

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

We know that

cos² θ + sin² θ = 1

⇒ sin² θ = 1 – cos² θ

⇒ sin θ = √(1 – cos² θ)

And Given that cos θ = x

⇒ sin θ = √(1– x²)

Fill in the blanks

(i) sin² θ cosec² θ = ……..

(ii) 1 + tan² θ = ……

(iii) Reciprocal sin θ. cot θ = ……

(iv) 1–.......= cos²θ

(v)

(vi)

(vii) cos θ is reciprocal of .........

(viii) Reciprocal of sin θ is.........

(ix) Value of sin θ in terms of cos θ is

(x) Value of cos θ in terms of sin θ is

If sin θ= p and cos θ = q, what is the relation between p and q ?

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

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