Question

If f(x) =tan(2x) then f'(pi/6)?

Answer 1

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Answer 2

f ( x ) = tan ( 2 x );
f ` ( x ) = (1 / cos² x )· ( 2 x )` = 2 / cos² x
f` ( π/6 ) = 2 / cos² (π/6) = 2 / (√3/2)² = 2 : 3/4 =  8/3