Q1 of 48 Page 86

Find the values of the following:

(i)


(ii)


(iii)


(iv)

Note:

cos (90˚ – θ) = sin θ

Sin (90˚ – θ) = cos θ



(i) ⇒ cos 37˚ = cos (90˚ – 53˚)


    ⇒ cos 37˚ = sin 53˚


   ⇒ = = 1.

Therefore,  = 1

(ii) cosec 32˚ = cosec (90˚ – 58˚)


   ⇒ cosec 32˚ = sec 58˚


      ⇒ = = 1.

Therefore,  = 1


(iii) tan 10˚ = tan (90˚ – 80˚)


   ⇒ tan 10˚ = cot 80˚


   ⇒ = = 1.


Therefore,  = 1

(iv) cos 19˚ = cos (90˚ – 71˚)


   ⇒ cos 19˚ = sin 71˚


   ⇒ = = 1.

Therefore,   = 1

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