ACT Math · Polynomial and rational functions
What are the vertical asymptotes of f(x) = (x+2)/(x²-16)?
What are the vertical asymptotes of ?
Answer and explanation
Answer: A: x = 4 and x = -4
A vertical asymptote occurs where the denominator is zero and the factor does not cancel with the numerator. Set to get , so or . The numerator, , is not zero at either value, so nothing cancels and both are asymptotes, choice A. Choice B () is where the numerator is zero, which gives an -intercept, not an asymptote. Choice C () confuses with . Choice D ( only) finds just one of the two roots of .
More Polynomial and rational functions questions
- Question 12One solution to x³ - 2x² - 5x + 6 = 0 is x = 1. What is the sum of the other two solutions?
- Question 16What is the domain of f(x) = √(x-4)x-7?
- Question 21For the function f(x) = (x²-16)/(x-4), what is the value that f(x) approaches as x approaches 4,…
- Question 93What are all real solutions to x³ + 2x² - 9x - 18 = 0?
- Question 96What is the quotient when x³ - 2x² - 5x + 6 is divided by x - 1?
- Question 103What values of x must be excluded from the domain of f(x) = (x+5)/(x²-9)?
Learn the method behind questions like this one
The ACT Math course teaches each tested skill through lessons, step-by-step solutions to sample problems, the complete study guide and full-length practice tests.