Question

(c) Find the value of 13 tan 12° cot 45° cot 60° tan 78°.
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Answer 1

Answer:

tan 12 and cot 78 will become 1 as tan (90-theta) = cot theta

Then 13 × 1 × cot 45 × cot 60

Put the value of cot 45 and cot 60

Cot 45 = 1 and Cot 60 = 1/ root3

therefore we get

13×1×1×1/root3

13/ root 3

By rationalizing we get

13root3 /3