pls check my answer

[Shoppingal]

Expand and simplify. Express the equation in standard form.

f(x) = -2(x-1)(x+4)(x+1)(x-3)
= -2(x^2 + 4x -x-4)(x^2-3x+x-3)
= -2(x^2+3x-4)(x^2-2x-3)
= -2(x^4-2x^3-3x^2+3x^3-6x^2-9x-4x^2+8x+12)
= -2(x^4+x^3-13x^2-x+12)
= -2x^4-x^3+26x^2+2x-24

Thank you

 

[Deleted member 4993]

Expand and simplify. Express the equation in standard form.

f(x) = -2(x-1)(x+4)(x+1)(x-3)
= -2(x^2 + 4x -x-4)(x^2-3x+x-3)
= -2(x^2+3x-4)(x^2-2x-3)
= -2(x^4-2x^3-3x^2+3x^3-6x^2-9x-4x^2+8x+12)
= -2(x^4+x^3-13x^2-x+12)
= -2x^4-x^3+26x^2+2x-24

Thank you

Looks good to me .... unless you and I made the same mistake/s

 

[mmm4444bot]

You had both better check the coefficients in your result! :cool:

(All of the work up to that point looks correct to me.)

By the way, you have expanded and simplified. I'm not sure about their meaning "standard form" here.

 

[HallsofIvy]

Expand and simplify. Express the equation in standard form.

f(x) = -2(x-1)(x+4)(x+1)(x-3)
= -2(x^2 + 4x -x-4)(x^2-3x+x-3)
= -2(x^2+3x-4)(x^2-2x-3)
= -2(x^4-2x^3-3x^2+3x^3-6x^2-9x-4x^2+8x+12)
= -2(x^4+x^3-13x^2-x+12)
= -2x^4-x^3+26x^2+2x-24

Thank you

If x= 1, this is - 2- 1+ 26+ 2- 24= -1+ 2- 1 while the original product would be -2(0)(5)(2)(-2)= 0.