Posted by **Anonymous** on Tuesday, June 8, 2010 at 8:39pm.

f(x) = x3 + 2x2 – 0.4X – 1

how do you you factor this?

- Math 209 -
**Reiny**, Tuesday, June 8, 2010 at 8:49pm
Do not repost a question which has been answered.

http://www.jiskha.com/display.cgi?id=1276043019

- Math 209 -
**drwls**, Tuesday, June 8, 2010 at 8:54pm
Please use ^ before exponents.

There is no simpl standard formula for finding the roots of cubic equations. First create integer coefficients by rewriting as

(1/5) (5x^3 + 10x^2 -2x -5)

There are no simple factors with integers for this equation. That can be proven with something sometimes called the "p/q theorem". It can be faotored to

f(x) = 5[(x-0.689)(x+1.941,(x+0.748)]

I used an online solver for that.

The numbers in the factors are rounded.

## Answer this Question

## Related Questions

- Math 209 - f(x) = x3 + 2x2 – 0.4X – 1 how do you you factor this?
- Algebra - Solve. (–10x3 + 30x – 20) ÷ (–5x + 5) • 2x2 – 2x + 4 • –2x2 – 2x – 4...
- Factor - How do I factor these: 2x2 - 16x + 30 4x^2-9 x^2-5x 5x^2-26x+5 25x^2+4 ...
- Math - factor 2x2 - x - 3
- Math 209-College Mathematics II - How do you factor this completely: x^3 + ax + ...
- Math 209 - When simplifying a rational fraction, why do you need to factor the ...
- math (algerba 1) - 2x2 + 16x + 32 how do I Factor and label? And how do I know ...
- Algebra - If the sides perpendicular to the wall have length x feet, which of ...
- biology - How can an understanding of the "mortality factor" lead to a ...
- math - graph y=x2,y=2x2 and y=1/2x2 on the same