Question

Question #aee9f

Answer 1

we have an identity,
`sin(x+y) = sinxcosy + cosxsiny`

`=>Sin ((5pi)/7) cos (pi/3) + sin (pi/3) cos ((5pi)/7)`
`=> sin ((5pi)/7+pi/3)`
`=>sin((15pi+7pi)/21)`
`=>sin((22pi)/21)`
`=>sin(pi + pi/21)`
`=> - sin(pi/21)`