Maths question

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

2013-06-21 22:42:52 補充：
One more question,
What is the requirement of your question?

If it is simple factorization,
I have done it for you.

If it is quadratic equation
The answer should be
x=-1 or √(2) - 1 or -√(2) - 1

2013-06-21 22:47:32 補充：
The answer given by 002 is simple expansion.

I think 忍 does know the answer if the question just requires 忍 to expand it

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

Sorry there is only one step, so this is the answer