Thursday

August 21, 2014

August 21, 2014

Posted by **Enlia** on Monday, October 15, 2012 at 9:02pm.

- Math Rational Functions-Please Clarify =) -
**Reiny**, Monday, October 15, 2012 at 10:31pmHere is a wonderful webpage that let's your graph just about any curve

http://rechneronline.de/function-graphs/

enter your function with brackets in the form

(2x^2-18)/(x^2+3x-10)

set: "range x-axis from" -20 to 20

set: "range y-axis from" -20 to 20

you will see your y-intercept correct at (0,1.8)

and the two vertical asymptotes of x = -5 and x = 2

starting to show.

Horizontal asymtotes begin to show up only when x approaches ± infinity, so if you look to the far right, the curve approaches y = 2 from the bottom up, and if you look far to the left, the curve approaches y - 2 from the top down

**It is very common for the curve to intersect the horizontal asymptote for reasonable small values of x.**

If we set our function equal to 2,

(2x^2-18)/(x^2+3x-10) = 2 , and cross-multiply we get

2x^2 - 18x = 2x^2 + 6x - 20

-24x =-20

x = 20/24 = 5/6 , which is shown on the graph

But as x --> ±∞ , the function will never again reach the value of 2

(try it on your calculator, set x = 500 and evaluate

then let x = -500 and evaluate,

in the first case you should get 1.988... a bit below 2

in the 2nd case you should get 2.012... a bit above 2

the larger you make your x, the closer you will get to 2, but you will never reach it, and that is your concept of an asympote )

- Math Rational Functions-Please Clarify =) -
**Enlia**, Monday, October 15, 2012 at 10:56pmThank you very much!

- Math Rational Functions-Please Clarify =) -
**Reiny**, Monday, October 15, 2012 at 10:58pmyou are welcome,

does it make sense now?

- Math Rational Functions-Please Clarify =) -
**Enlia**, Tuesday, October 16, 2012 at 4:49pmYes it does ^^

**Related Questions**

Gr.11 - Rational functions graphing. - 1. Identify a rational function whose ...

Math - Suppose f is a function with range (-∞,∞) and g is a function...

Math - Verify these answers :] Would be thankies~ 1. Determine the intervals in ...

Calculus - We're learning about different kinds of functions and I don't really ...

Math - State the range of the function: f(x) = 5ex + 1 A) (0, ∞) B) (1...

math - hello, i have some question about rational functions. 1) are there any ...

Math - Can someone help me with these T.T 1.Which polynomial function would have...

Math- Rational Functions - 1. Some rational functions have asymptotes, others ...

Math - For the given functions, write the rational function, r(x) = [f(x-h)-f(x...

****college algebra…radical functions**** - Create a rational function such that...