How do you find #\sin \frac { 11\pi } { 6}#?

2 Answers
Jun 24, 2018

The answer is #=-0.5#

Explanation:

We need

#sin(a+b)=sinacosb+sinbcosa#

#sin(pi)=0#

#cos(pi)=-1#

#sin(5/6pi)=sin(1/6pi)=1/2#

Therefore, one way is

#sin(11/6pi)=sin(pi+5/6pi)#

#=sin(pi)cos(5/6pi)+cos(pi)sin(5/6pi)#

#=0*(-sqrt3/2)-1*1/2#

#=-1/2#

#=-0.5#

Jun 24, 2018

#color(indigo)(sin ((11pi) / 6) = sin (-pi/6) = -1/2 = -0.5#

Explanation:

#sin ((11pi) / 6)#

#=> sin (-2pi + (11pi)/6)#

#color(indigo)(=> sin (-pi/6) = sin (-30^@) = -1/2 = -0.5#