Basic c2 graphs question

Say you are given the equation y = x(x^2-1) to sketch the roots are (-1,0) (0,0) (1,0)

How would you sketch it I mean in terms of which side would you start of with how do you know where the max min points are.

Also does anybody know what the graph of y=-srt of x look like?

Say you are given the equation y = x(x^2-1) to sketch the roots are (-1,0) (0,0) (1,0)

How would you sketch it I mean in terms of which side would you start of with how do you know where the max min points are.

Also does anybody know what the graph of y=-srt of x look like?

I forgot to answer your other question about max/min points.

Max/min occurs at stationary points where the gradient is equal to zero.

$y=x(x^2-1) = x^3-x$

Differentiate the above expression, and set dy/dx=0 to find the stationary points. Find the 2nd derivative to check whether the points are max or min.

The graph of $y= - \sqrt{x}$ looks like this:



For the graph of, $y=x(x^2-1)$

You know the values where it crosses the x-axis, just consider all the regions, by subbing in some values to deduce the shape of the graph.

e.g. It crosses at (1,0), see what is the value of y when x=2, if it is positive then the graph will move upward and if it is negative, then the graph will move downwards.