This seems like a hairy integral. Now the key insight here is to realize that you have this expression x to the fourth plus 7 and you also have its derivative up here. The derivative of x to the fourth plus 7 is equal to 4x to the third. The derivative of x to the fourth is 4x to the third. The derivative of 7 is just 0. So that's a big clue that u-substitution might be the tool of choice here. I'll just write u. I'll write the whole thing.