Hi i need some help please,,

Im going integration,

i have done the first question = (ment to b a math symbol like a f with no stick)S^2 and^1 2xdx which indifferentated =2^2-1^2 = 3 and got the right answer.

But then i tried to do the others but they arent working out..

s^3 & ^0 2xdx = x^2, then 2^3-0^2 which =8 but the answe is 9..:S

But then there are some with brackets in and i dont know how to go about those help please.

s^6 ^5 (2x+1)dx ...

Thank you