###### Asked in Math and ArithmeticAlgebra

Math and Arithmetic

Algebra

# How do you solve 4x3 equals 12x2-x-3 equals 0?

## Answer

###### Wiki User

###### June 22, 2010 3:38AM

4x3= 12x2-x-3

The answers are x= -.4324426. or x= .6157299 or x= 2.816713

These are approximations.

## Related Questions

###### Asked in Math and Arithmetic, Algebra, Calculus, How To

### How to solve 4x3 plus 0.4x2 plus 0.01x-2.4x10-18 equals 0?

There are a number of ways. One possibility is the iterative
method.
Rewrite the equation so as to make x the subject:
4x3 + 0.4x2 + 0.01x - 2.4*10-18 = 0
4x3 = 2.4*10-18 - 0.4x2 - 0.01x
x3 = (2.4*10-18 - 0.4x2 - 0.01x)/4 x = cuberoot[(2.4*10-18 -
0.4x2 - 0.01x)/4]
The original equation is approximately equal to
4x3 + 0.4x2 + 0.01x = 0
or x*(20x - 1)2 = 0
which has roots at x = 0 and x = -0.05
Start with a value, x1 near one of these roots and use the
iteration:
xn+1 = cuberoot[(2.4*10-18 - 0.4xn2 - 0.01xn)/4] where n = 1, 2,
3, etc to improve your estimates.
The resulting roots are, not surprisingly, 0 and -0.05 to 10
decimal places.