If you would like to simplify (3x^2 - 2) * (5x^2 + 5x - 1), you can calculate this using the following steps:
(3x^2 - 2) * (5x^2 + 5x - 1) = 3x^2 * 5x^2 + 3x^2 * 5x - 3x^2 * 1 - 2 * 5x^2 - 2 * 5x + 2 * 1 = 15x^4 + 15x^3 - 3x^2 - 10x^2 - 10x + 2 = 15x^4 + 15x^3 - 13x^2 - 10x + 2
The correct result would be 15x^4 + 15x^3 - 13x^2 - 10x + 2.