Question

2)If triangle RPQ is a right angled triangle at Q. If PQ = 5cm and RQ = 10 cm,find (i) sin ^2 P (ii) cos ^2 R and tan R (iii) sin P X cos P (iV) sin ^2 P –cos ^2p

Answer 1

Answer:  (i) 1       (ii) 3/4 , √3/3       (iii) 0       (iv) 1

Step-by-step explanation:

ΔRPQ is 1 30°-60°-90° triangle because RQ = 2PQ , where

• ∠R = 30°
• ∠P = 90°
• ∠Q = 60°

(i) sin² (90°) = 1² = 1

$\text{(ii)}\ \cos ^2(30^o)= \bigg(\dfrac{\sqrt3}{2}\bigg)^2=\dfrac{3}{4}$

$.\quad \tan (30^o)=\dfrac{1}{\sqrt3}\bigg=\dfrac{\sqrt3}{3}$

(iii) sin (90°) × cos (90°) = 1 × 0 = 0

(iv) sin² (90°) - cos² (90°) = 1² - 0² = 1