thanx- college algebra
2007-07-09 09:40:21 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
-x^3+3x+2
-(x^3-3x-2)
-(x-2)(x+1)^2
2007-07-09 09:45:34 · answer #1 · answered by Nate M 2 · 1⤊ 0⤋
We can use the factor theorem to factorise the above expression.
Let f(x) = -x^3 + 3x +2
Try x = -1, f(-1) = -(-1)^3 + 3*(-1) + 2
f(-1) = 1-3+2
f(-1) = -2 + 2
f(-1) = 0
Since f (-1) = 0, then x + 1 is a factor of f(x) according to the factor theorem.
Then,
-x^3 + 3x +2
= (x+1) * (-x^2 + x + 2)
= (x+1) * (-x+2)* (x+1)
= (x+1)* (2-x)* (x+1)
= (x+1)^2 * (2-x)
2007-07-10 01:45:25 · answer #2 · answered by Anonymous · 0⤊ 0⤋
=-(x-2)(x^2+2x+1) = -(x-2)(x+1)^2
2007-07-09 09:56:00 · answer #3 · answered by ironduke8159 7 · 0⤊ 0⤋
-x^3+3x+2=
-x^3+3x+3-1=
-(x^3+1)+3(x+1)=
-(x+1)(x^2-x+1)+3(x+1)=
-(x+1)(x^2-x+1-3)=
-(x+1)(x^2-x-2)=
-(x+1)(x^2-x-1-1)=
-(x+1)[(x^2-1)-(x+1)]=
-(x+1)[(x+1)(x-1)-(x+1)]=
-(x+1)[(x+1)(x-1-1)]=
-(x+1)(x+1)(x-2)=
(x+1)^2*(2-x)
2007-07-09 09:49:20 · answer #4 · answered by cvet_che 2 · 2⤊ 1⤋