Inverse Variation
The Parent Function
Transformation Station
Asymptote Rules
Intercepts & Complex Features
100

In this type of variation, as one variable increases, the other decreases.

What is inverse variation?

100

These are the vertical and horizontal asymptotes for the parent function f(x)=1/x.

What are x=0 and y=0? 

100

In the function, this is the value of the parameter h.

g(x)=3(1/{x-4})+1

What is 4? 

100
This is the horizontal asymptote (y=) whenever the degree of the denominator is larger than the degree of the numerator.
What is y=0? 
100

To find this feature, you must evaluate the function at f(0). 

What is the y-intercept?

200

This is the specific formula used to find the constant of variation (a) when given a coordinate (x, y).

What is a=xy?

200

These two specific coordinates are the standard "reference points" for the parent function.

What are (-1, -1) and (1, 1)? 

200

This is the horizontal asymptote for the function 

g(x)=3(1/{x-1})+2

What is y=2.

200

This is how you find the horizontal asymptote when the degrees of the numerator and the denominator are equal. 

What is the ratio of the leading coefficients (y=a/b)?

200

To find the x-intercept of a rational function, the shortcut to solve is to set this specific part of the function equal to zero and solve for x. 

What is the numerator? 

300

If you are traveling 60 miles, this is the travel time if your speed is 120 mph. 

What is 0.5 hours (or 30 minutes)?

300

This is the domain of the parent function f(x)=1/x.

what is x does not equal 0? 

300

These are the three transformations occurring in the function compared to the parent function. 

f(x)=3(1/{x-1})+2

What are a vertical stretch of 3, shift right 1 and shift up 2?

300

This is the horizontal asymptote for the function 

y={6x-2}/{2x+1}

What is y=3?

300

For the function, this is the x-intercept. 

f(x)={x+6}/{x^2-1}

What is (-6, 0)? 

400

Given the coordinate (4, 3), and knowing x and y vary inversely, this is the resulting equation for y. 

What is y=12/x?

400
Of the four paramaters (a, b, h, k), these are the only two that affect the location of the asymptotes. 

What are h and k. 

400

This is the mathematical process used to rewrite a function like what you see below in the form given. 

y={2x+3}/{x+1}

y=a(1/{x-h})+k

What is long division? 

400

To find the vertical asymptotes of a complicated rational function, you must set this part of the fraction to zero and solve. 

What is the denominator? 

400

These are the two vertical asymptotes for the function 

f(x)={4x+16}/{x^2-9}

What are x=3 and x=-3? 

500

In the context of travel where distance is the constant, this is the constant of variation if you travel at 30 mph for 2 hours. 

What is 60? 

500

This is the formula used to calculate the "positive" transformed reference point using parameters b, h, a, and k. 

What is (b+h, a+k)? 
500

Using long division, the function rewrites to this specific tranformation form. 

y={2x+3}/{x+1}

y=1/{x+1}+2

500

This is the horizontal asymptote for the function 

y={x^4+3x^2+10x-4}/{x-1}

What is none?

500

For a rational function, these are the three general sections you must test points in to draw an accurate graph. 

What are the left, middle and right sections?