Saturday

October 25, 2014

October 25, 2014

Posted by **Amy~** on Sunday, September 26, 2010 at 1:14am.

would become x(x^2-3x)

then how would I graph this?

- Math Graphing -
**Reiny**, Sunday, September 26, 2010 at 7:19amx(x^2-3x) < 0

x^2(x-3) < 0

critical values of x=0 , x=3

on a number line, mark x=0 and x=3, splitting the line into 3 parts

1. x<0

pick any number < 0, say x=-5

(+)(-) < 0 , that's what we want

2. 0 < x < 3 , pick a value, let's pick x = 1

(+)(-) < 0 , good !

3. x> 3, let x=5

(+)(+) > 0 , no good

so x < 3 will work.

another way is know what a general cubic looks like

you would have

y = x^2(x-3)

there would be double root at x=0, so it touches at x=0 without crossing, and it crosses at x = 3

easy to sketch, one can see that the curve is below the x-axis for x< 0 as well as between 0 and 3.

so that is our domain, namely x < 3

**Answer this Question**

**Related Questions**

math (graphing) - I need to graph "y = -2x+5" and "y = 4/5x-3"... I don't think ...

graphing math (last ones) ill figure out the rest - how would u graph y=3/2x+4 ...

Math - If I were to graph 20a+34b is greater than or equal to 240, which would ...

MATH _ GRAPHING RATIONAL FUNCTIONS - When graphing rational functions, how do I ...

math-graphing - How would I graph the equation y=6?

math-graphing - y>-5 x>6 How would I get ordered pairs to graph this?

graphing question - Write the equation of the line with slope 4 and y-intercept...

Math - I have a TI-83 graphing calculator. How do you graph a polar equation on ...

graphing math - how would u graph y=3/2x+4 sorry im not good at fractions

math - Find an algebraic model for the sum of a number and its reciprocal. I ...