To draw a cubic function
To draw a cubic function,you need to find the following information:3 x intercepts,and is the cubic positive or negative.
given the function:x³-7x+6
Step 1.factor it.
We factor this function into y=(x+3)(x-2)(x-1).You can use any method。
Step 2.Label them on the graph.
Label all the X intercepts onto the graph
Step 3.Positive or negative
Check the function see if it is negative,or positive.This function is positive.A good way to check it is to check the sign of term A.
Step 4.connect them
After check the sign,then we can joint the dots with cruves.Remember the rules?Positive left to right,negative from right to left.So in this case,we draw a line from the left down corner,and touch the x intercept (-3,0),then the cruve goes up to the vertex between (-3,0)(1,0),and goes down to the vertex between (1,0)(2,0).At last,the cruve goes all the way to the upper right hand corner.A cubic function is graphed
This is the picture of it.