Question

find the value of sin-1(cos 43pie/5)​

Answer 1

>sin-1 [cos (8pi+3pi/5)]

=>sin-1 [cos (3pi/5)]

=> sin-1 [cos (pi/2+pi/10)]

=> sin-1 [-sin(pi/10)]

=>-sin-1 [sin(pi/10)]

=>-pi/10