Before starting, there's a formula that will be crucial to solving all this.
The formula states the following:
Polynomial 1:
Use the formula shown in the beginning of this answer.
Now, we only have to simplify each term. Since you're tackling problems such as these, you should be familiar on exponential rules, so I hope you can follow along.
Polynomial 2:
Use the formula shown in the beginning of the answer
Polynomial 3:
Use the formula shown in the beginning of the problem (pretty much the same for 3 terms as well).
If you have any comments/questions, feel free to comment and I'll be happy to clarify.