You are completely correct.
R is the region below the curve y=x and above the x-axis from x=0 to x=b; where b is a positive constant.
S is the region below the curve y=cos (x) and above the x-axis from x=0 to x=b. for what value of b is R equal in area to the area of S?
so I know this means
So do I solve ?
If so I ge t 1.402