What is the exact value of Sin^2 (pi/6) - 2sin (pi/6) cos (pi/6) + cos^2 (-pi/6)?

1 Answer
Feb 18, 2016

Value is (1-sqrt3/2)

Explanation:

To solve this we need value of sin(pi/6), cos(pi/6) and cos(-pi/6). As sin(pi/6)=1/2 and cos(pi/6)=cos(-pi/6)=sqrt3/2, putting these

sin^2(pi/6)−2sin(pi/6)cos(pi/6)+cos^2(−pi/6)

=(1/2)^2-2*1/2*sqrt3/2+(sqrt3/2)^2

=1/4-sqrt3/2+3/4

= 1-sqrt3/2