Answer:
The y-intercept is (0,0)
The x-intercepts are (-3,0), (0,0), and (4,0)
Step-by-step explanation:
So we have the function:
[tex]f(x)=-x^3+x^2+12x[/tex]
And we want to solve for the x- and y-intercepts.
Y)
To solve for the y-intercept, recall that the y-intercept is when the graph touches the y-axis. At that point, the x values is 0. Thus, to find the x-intercept, substitute 0 for x:
[tex]f(x)=-(0)^3+(0)^2+12(0)[/tex]
Simplify:
[tex]f(x)=0[/tex]
So, the y-intercept is (0,0)
X)
To solve for the x-intercept(s), set the function equal to 0 and solve for x:
[tex]0=-x^3+x^2+12x[/tex]
First, factor out a negative x:
[tex]0=-x(x^2-x-12)[/tex]
Factor within the parentheses:
[tex]0=-x(x-4)(x+3)[/tex]
Zero Product Property:
[tex]-x=0\text{ or } x-4=0\text{ or } x+3=0[/tex]
Divide by -1 on the first one. Add 4 on the second one. And subtract 3 on the right:
[tex]x=0\text{ or } x=4\text{ or } x=-3[/tex]
So, our x-intercepts are:
[tex](-3,0), (0,0), (4,0)[/tex]
And we're done :)