Question

Determine the end behavior of each rational function below. f(x) = 7x5 − 3x + 1 / 4x3 + 2

Answer 1

Answer:

When x ⇒ +∞ and x ⇒ -∞, f(x) ⇒ +∞

Step-by-step explanation:

Hi there!

First, let´s write the function:

f(x) = (7x⁵ - 3x +1) / (4x³ + 2)

When x ⇒ +∞

f(x) ⇒ (7x⁵ - 3x) / 4x³    because (7x⁵ - 3x)>>>1 and 4x³>>>2 we can neglect those constants.

f(x) ⇒7x⁵/4x³ - 3x/4x³

f(x) ⇒ 1.75x² - 0.75/x²    (0.75/x² ⇒ 0 because a number divided by a very big number is approximately zero). Then:

f(x) ⇒ 1.75x² ⇒ +∞

When x ⇒ -∞

f(x) ⇒ 1.75x² = +∞ (because x² is always positive)

Then, when x ⇒ +∞ and x ⇒ -∞, f(x) ⇒ +∞