How do you evaluate tan(π2+π6).cot(ππ6).cos(π2π6)?

1 Answer
Aug 13, 2016

Using identities for tan(A+B) and cos(A+B)

Explanation:

So tan(A-B)= tanA-tanB(1+tanAtanB)
So cot(A-B) will be the reciprocal - (1+tanAtanB)tanA-tanB
So A- π and B is π6
So =

"(tan(2π3)" x "(cos(π3))"x ("(1+tan(π)tan(-pi/6)))/tan(pi)tan(-pi/6)

= 3 x 12 x (130+1)/013

Solving will give 1.5