Answer:

1. (x+1)(x+3)(x-2)

2. (x+1)²(x-1)

3. (x+1)(x+2)(x-4)

Step-by-step explanation:

1. x³+2x²-5x-6

x³+x²+x²-5x-6

x³+x²+x²+x-6x-6

x²(x+1)+x(x+1)-6(x+1)

(x+1)(x²+x-6)

(x+1)(x²+3x-2x-6)

(x+1)[x(x+3)-2(x+3)]

=(x+1)(x+3)(x-2)

2. x³+x²-x-1

x²(x+1)-x-1

x²(x+1)-(x+1)

(x+1)(x-1)(x+1)

=(x+1)²(x-1)

3. x³-x2-10x-8

x³+x²-2x²-10x-8

x³+x²-2x²-2x-8x-8

x²(x+1)-2x(x+1)-8(x+1)

(x+1)(x²-2x-8)

(x+1)(x²+2x-4x-8)

(x+1)[x(x+2)-4(x+2)]

=(x+1)(x+2)(x-4)