How can you use polynomial identities to multiply expressions ?

The correct answer is: Thus, the expansion is: .

Hint:
Let a and b be variables or real numbers, then:
We are asked to explain how you can use the polynomial identities to multiply expressions.
Step 1 of 2:
Here, the given expression is , where .
So, we can use the identity to find the expansion of  .
Step 2 of 2:
Apply the polynomial identity,  to get the answer of  Thus, we have:

Thus, the expansion is: 
Note:
Any expression of the form  can be expanded using the identity rather than using the conventional and time taking method of multiplying them, .