# factoring...

Discussion in 'Physics & Math' started by qfrontier, Mar 3, 2002.

1. ### qfrontierCaptain Of StarshipRegistered Senior Member

Messages:
114
factoring...another question (edited)

How would you find the value of x for the quadratic equation of :

6x^2+3x-2=0

ps. Ive found a solution but im not sure if its the solution...any help appreciated.

Last edited: Mar 10, 2002

3. ### AntonRegistered Member

Messages:
8
Hmm..well my calculator does it quite well

and finds that the factors are -1.542575695 and 7.582575695 and that the min is non existant (its a parabola so that is a given) and the max is 7. Hope that helps. If u wanted to do it yourself, simply use the quadratic equation:

x=-b +/- sqrrt(b^2-4ac)
---------------------------
2a

and use the derivative of the equation to find the max

-Anton

5. ### James RJust this guy, you know?Staff Member

Messages:
38,340
y=-1/3x^2 + 2x + 4

Take out the -1/3 factor.

= -1/3 (x^2 - 6x - 12)

Complete the square.

= -1/3 (x^2 - 6x + 9 - 12 - 9)

= -1/3 ((x - 3)^2 - 21)

Put the -1/3 back in.

= -1/3 (x - 3)^2 + 7

The maximum is y=7, which occurs at x=3.