Evaluate: x(x + 1)(x - 1)

I think I did this right.

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

x^2 + 1x + x^2 + -1x

x^2 + 1x^3 + -1x

x^2 - 1x^4 <-- is this right?

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- Jul 6th 2005, 06:11 PMHayabusaIs this right?
Evaluate: x(x + 1)(x - 1)

I think I did this right.

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

x^2 + 1x + x^2 + -1x

x^2 + 1x^3 + -1x

x^2 - 1x^4 <-- is this right? - Jul 6th 2005, 06:23 PMMathGuruFOIL method
x(x + 1)(x - 1)

is the same as

x[(x + 1)(x - 1)], so lets do what is inside the brackets first.

Using FOIL method (FOIL is First Outer Inner Last, ask me if you need clarification)

x[x^2 - x + x - 1]

- x + x cancels, now distribute the x

**x^3 - x**<---ANSWER - Jul 6th 2005, 06:31 PMHayabusa
Thank you for the help.