Evaluate the following trigonometry questions?

(i) (sin 18°)/(cos 72°)
= (sin 18°)/(cos 72°) = cos (90° – 18°))/(cos 72°) [∵ cos (90° – θ) = sin θ]
= (cos 72°)/(cos 72°) = 1

(ii) (tan 26°)/(cot 64°)
= (tan 26°)/(cot 64°) = (cot (90° – 26°))/(cot 64°) [∵ cot (90° – θ) = tan θ]
= (cot 64°)/(cot 64°) = 1

(iii) cot 48° – sin 42°
= cot 48° – sin 42° = cos 48° – cos (90° – 42°) [∵ cos (90° – θ) = sin θ]

(iv) cosec 31° – sec 59°
cosec 31° – sec 59° = cosec 31° – cosec (90° – 59°) [∵ cosec (90° – θ) = sec θ]
= cosec 31° – cosec 31° = 0

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