express cot (-3888) as a ratio of acute angle??

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Solution

cot(-3888) = -cot(3888) = -cot(21π + 108 )
Hence - cot(21π + 108 ) = -cot(108)
As cot(nπ + x ) = cot(x)
-cot(108) = -cot(π/2 + 18 ) = -(-tan(18)) = tan18 (ans)
As in the second quadrant tan and cot is negative .

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express cot (-3888) as a ratio of acute angle??

cot(-3888) = -cot(3888) = -cot(21π + 108 ) Hence - cot(21π + 108 ) = -cot(108) As cot(nπ + x ) = cot(x) -cot(108) = -cot(π/2 + 18 ) = -(-tan(18)) = tan18 (ans) As in the second quadrant tan and cot is negative .

cot(-3888) = -cot(3888) = -cot(21π + 108 )
Hence - cot(21π + 108 ) = -cot(108)
As cot(nπ + x ) = cot(x)
-cot(108) = -cot(π/2 + 18 ) = -(-tan(18)) = tan18 (ans)
As in the second quadrant tan and cot is negative .