Q5 of 48 Page 86

Find the values of the following:

(i) tan 12° cot 38° cot 52° cot 60° tan 78°


(ii) tan 5° tan 25° tan 30° tan 65° tan 85°

(i) tan 12˚.cot (90˚ – 52˚)cot 52˚cot 60˚tan (90˚–12˚)


⇒ tan 12˚cot 12˚ tan 52˚ cot 52˚ cot 60˚


⇒ tan 12˚××tan 52˚××


⇒


(ii) tan 5˚× tan 25˚× ×tan (90˚ – 25˚)tan (90˚–5˚)


⇒ tan 5˚×××tan 25˚×


⇒ 1× 1


=


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