Thread: polynomials

1.(5x2)(–2x3)
2.(x+3)(x+2)
3.(4x^2-4x-7)(x+3)
4.(x+2)(x^3+3x^2+4x-17)

Originally Posted by william

1.(5x2)(–2x3)
2.(x+3)(x+2)
3.(4x^2-4x-7)(x+3)
4.(x+2)(x^3+3x^2+4x-17)

1. -10x^5 because you multiply then add the exponents because the rule for multiplying exponents is to add them together

Originally Posted by william

1.(5x2)(–2x3)
2.(x+3)(x+2)
3.(4x^2-4x-7)(x+3)
4.(x+2)(x^3+3x^2+4x-17)

2. use FOIL

x^2+2x+3x+6
x^2+5x+6

Originally Posted by william

1.(5x2)(–2x3)
2.(x+3)(x+2)
3.(4x^2-4x-7)(x+3)
4.(x+2)(x^3+3x^2+4x-17)

3.4x^2(x)-4x(x)-7(x)+4x^2(3)-4x(3)-7(3)
=4x^3-4x^2+12x^2-7x-12x-21
=4x^3+8x^2-19x-21

Originally Posted by william

1.(5x2)(–2x3)
2.(x+3)(x+2)
3.(4x^2-4x-7)(x+3)
4.(x+2)(x^3+3x^2+4x-17)

4.x^3+3x^2+4x-17
x+2
=x^4+5x^3+10x^2-9x-34

thank you very much!