How do you sketch the general shape of f(x)=x^3-10x^2+33x-38 using end behavior?

1 Answer
Feb 10, 2017

See explanation.

Explanation:

graph{x^3-10x^2+33x-38 [0, 5, -5, 5]}

Polynomials x^n+a_1x^(n-1)+..+a_n are differentiable,

for x in (-oo, oo).

Here, as x to +-oo, f=x^3(1-10.x=33/x^2-38/x^3) to +-oo

The not-to-scale graph above reveals turning points and point of

inflexion..

f' =3x^2-20x+33=0, at x= 3 and 11/3

f''=6x-20=0, at x = 10/3. Here, and everywhere, f'''=6 ne 0.

So, the POI is at x =10/3.

Overall rise-and-fall graph is inserted below.

graph{x^3-10x^2+33x-38 [-30, 20, -15, 10]}