Question

how do i find the critical points of sin x = 2/5 ?

Answer 1

this is an equation to be solved.
do you mean to find the critical points of sinx ?

Answer 2

the critical points of a function are where f'(x)=0 or f'(x) does not exist.
So take the derivative and set it = 0 to find the critical points.

Answer 3

can u show me how? do i need to inverse the sin to get x by itself?

Answer 4

its just that 2/5 is not a even pi value...