Q2 of 48 Page 86

Find the values of the following:

(i) cosec 25° – sec 65°


(ii) cot 34° – tan 56°


(iii)


(iv) sin θ cos(90° – θ) + cosθ sin(90° – θ)

(i) cosec (90˚– 65˚) – sec 65˚


⇒ sec 65˚ – sec 65˚ (since, cosec (90˚ – θ) = sec θ)


= 0


(ii) cot (90˚ – 56˚) – tan 56˚


⇒ tan 56˚ – tan 56˚ (since, cot (90˚ – θ) = tan θ)


= 0.


(iii)


⇒


⇒ 1 – 1


= 0.


(iv) ⇒ sin θ.sin θ + cos θ.cos θ


⇒ sin2 θ + cos2 θ


⇒ 1.


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