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assman
Nov16-04, 03:59 PM
5x^3 - 2x^2 + 3

Where are the zeros. Is there one between [-1,1]

THanks.
UrbanXrisis
Nov16-04, 04:06 PM
There is a zero at (-0.7860031,0)
Justin Lazear
Nov16-04, 07:20 PM
Evaluate the expression at x = -1 and x = 1.

What are the signs of the expression at these two points? What does this tell you about whether or not there is at least one root between them (hint: plot the two points and draw a line through them. Does it cross 0?) ?

--J
dduardo
Nov16-04, 08:48 PM
UrbanXrisis, that is the wrong answer.
UrbanXrisis
Nov16-04, 10:21 PM
ACK! Sorry! (-0.7290014,0) Typed in the wrong answer
Tom McCurdy
Nov16-04, 10:49 PM
The easiest way to solve that for you might be to graph the equation. Then limit you window from in the x from -2 to 2 then see if it crosses the axis between -1 and 1... zoom out to see all the zeros if more exist.
Raza
Nov18-04, 06:09 PM
I think x would -0.92 if it is like this
5x^3 - 2x^2 + 3=0