#### (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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