Question

Which is the graph of the function f(x) = x3 – x2 – 17x - 15?

Answer 1

Answer with Step-by-step explanation:

We are given that a function

$f(x)=x^3-x^2-17x-15$

We have to find the graph of the given function.

y-intercept:It is that  value of y where the graph cut the y- axis.

Let

$y=f(x)=x^3-x^2-17x-15$

Substitute x=0

Then, we get

$f(0)=-15$

y-intercept of the graph=-15

x- intercept: It is that value of x where the graph cut the x- axis.

Substitute y=0

$x^3-x^2-17x-15=0$

Substitute x=-1

$-1-1+17-15=0$

Therefore,x=-1  is a solution of given equation.

$(x+1)(x^2-2x-15)=0$

$(x+1)(x^2-5x+3x-15)=0$

$(x+1)(x(x-5)+3(x-5))=0$

$(x+1)(x+3)(x-5)=0$

$\implies x=-1,-3,5$

Hence, the x-intercept are

-3,-1 and 5