dy Next we substitute 3x1/2 into the equation for the arc length function and simplify. dx s(x) = L* 1 + (f'(t)) dt 1+ 3 dt 3 = 1+9 t dt 9 Step 3 We have found the integral that defines the arc length function. To finish, we evaluate the definite integral. s(x) = 1 + 9t dt == 2 27