How do i solve this?

1. Oct 3, 2004

Gughanath

x^2+7x>6+2x^3...I tried many times..i cant solve this :grumpy: ...please help

2. Oct 3, 2004

Dr-NiKoN

x^2 + 7x > 6 + 2x^3 = -2x^3 + x^2 + 7x - 6 > 0

Try solving for:
-2x^3 + x^2 + 7x - 6 = 0

3. Oct 3, 2004

Gughanath

I cant solve that sorry...could you help any further?

4. Oct 3, 2004

Tide

I noticed the sum of the coefficients is 1 so (x-1) is a factor:

$$2x^3-x^2-7x+6 = (x-1)(x+2)(2x-3)$$

That should get you started!

5. Oct 6, 2004

aekanshchumber

try it,
x^2 + 7x>6x + 2x^3
or, 2x^3 - x^2 -x<0
or, x(2x^2 - x - 1)<0
this implies, either x<0 or (2x^2 - x - 1) <0
as the expression is negative which is only possible if one of the term is negative.

6. Oct 6, 2004

Integral

Staff Emeritus
You have read the problem incorrectly. It should read
$$x^2 + 7x > 6 + 2x^3$$

Last edited: Oct 6, 2004
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