If you have 2 one variable polynomials you want to add, subtract, or multiply, and see the math work behind it, or one polynomial you want to simplify by like terms, I've created this calculator for you. Each term box can handle 75 characters. I can expand that if somebody feels the need.
Essentially, terms with powers need to be entered like 2x^2. See instruction link at the top of the page. Each operation will take you through the math work to derive the terms, and then show the resulting interim steps.
I've done much testing on this, but please notify me of errors or changes you'd like to see. It is searchable by polynomial, algebra, add, subtract, multiply. Enjoy: