If you would like to calculate (3 * x + 2)^2 - (2 * x - 1)^2, you can do this using the following steps:
(3 * x + 2)^2 - (2 * x - 1)^2 =
9 * x^2 + 12 * x + 4 - (4 * x^2 - 4 * x + 1) =
9 * x^2 + 12 * x + 4 - 4 * x^2 + 4 * x - 1 =
5 * x^2 + 16 * x + 3
The result is 5 * x^2 + 16 * x + 3.