How To Draw A Cubic Graph Without Using A Calculator Example Draw y=x^3+2x from x=-2 to x=-2

In this video you will be shown how to draw a cubic graph. A cubic graph is one where the highest power of x is x^3 in the equation.

In the example given you are asked to draw the graph of y=x^3+2x from x=-2 to x=2. First draw out a table of values from x=-2 to x=2. All you need to do now us work out the y coordinates. Do this by substituting the x coordinates into the equation. It’s probably best to start with the positive x values first as the negative ones will be more difficult to calculate.

For example, to find the y coordinate at x=2, substitute this into the equation to give y=12, since 2^3+2x2=8+4=12. Once all the y coordinates have been found, plot the points on the coordinate grid and draw a smooth curve without a ruler.