(i) cos 18°/sin 72°
(ii) tan 41°/cot 49°
(iii) cosec 17°30’/sec 72°30’
Answer :
(i) cos 18°/sin 72°
= cos 18°/sin (90° – 18°)
= cos 18°/cos 18°
= 1
(ii) tan 41°/cot49°
= tan 41°/cot (90° – 41°)
= tan 41°/tan 41°
= 1
(iii) cosec 17°30’/sec 72°30’
= cosec 17°30’/sec (90° – 17°30’)
= cosec 17°30’/cosec 17°30’
= 1
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