Yes. And even beyond just u-substitution, it's extremely helpful to be able to know how to take derivatives in order to be able to check your work.

Integration is essentially taking derivatives backwards. So trying to calculate an integral without knowing how to calculate a derivative would be like trying to factor 15 into 3\*5 without knowing how to multiply 3\*5 to get 15.

The good news is that if you've seen the material once, it shouldn't take you very long to brush up on taking derivatives. Unlike integration, there's no guess-work involved in taking derivatives. If you have a product, you use the product rule. If you have a quotient, you use the quotient rule and so on. So you should be able to quickly get back to the point where you can find the derivative of any expression no matter how complicated.