Answer:
1. (3x - 2)(x + 5).
2. 2(x + 4)(x - 2).
3. (2x - 9)(2x + 9).
Step-by-step explanation:
1. f(x) = 3x^2 +13x -10
Try to factor by the ac method:
3 * -10 = -30
We need 2 numbers whose product is -30 and whose sum is + 13.
They are -2 and +15, so we write:
3x^2 + 15x - 2x - 10 Factor by grouping:
= 3x(x + 5) - 2(x + 5)
= (3x - 2)(x + 5).
2. f(x) = 2x^2+4x-16
= 2(x^2 + 2x - 8)
Now we need 2 numbers whose product is -8 and whose sum is + 2.
They are +4 and -2. So:
= 2(x + 4)(x - 2).
3. 4x^2 - 81 This is the difference of 2 squares so the factors are:
(2x - 9)(2x + 9).
