x is continuous and differentiable function
then max. and min. values p have the property:
there are two cases, first sin(x)=p with a constraint condition which
and when it happened, the value of function is max. Second,
the extreme value happened at cos(x)=0 ie x=2npi or (2n+1)pi
ie sin(x)=1 or -1 so, q=17/2, p=3/4 or -3/4
the first condition the max. value is
the min. value is :
solve the solution :