1. (x2-x-2) (x+3) 2.(3a2+b2)(a2-b2) 3.(x2-x-2)(x+3)

1. (x²-x-2)(x+3)
= x³ + 3x² -x² - 3x -2x -6
= x³ + 2x² - 5x - 6

2. ( 3a²+ b²)(a²-b²)
= 3a⁴ - 3a²b²+a²b² - b⁴
= 3a⁴ - 2a²b² - b⁴

3. sama seperti no 1