Posted by **Anonymous** on Monday, February 17, 2014 at 11:10pm.

find the inverse of the function

f(x) = x^2 − 6x, x ≥ 3

- pre-calc -
**Reiny**, Tuesday, February 18, 2014 at 12:00am
Your given function will be the part of the parabola which lies to the right of the vertex (3, -9)

so y = x^2 - 6x

inverse is

x = y^2- 6y

y^2 - 6y = x

complete the square:

y^2 - 6y+ 9 = x+9

(y-3)^2= x+9

y - 3= ± √(x+9)

y = 3 ± √(x+9)

but we only used the part for x≥3 of the original, so

the inverse is

f^-1 (x) = 3 + √(x+9) , x ≥ -9

check:

let x = 4

f(4) = 16 - 24 = -8

f^-1 (-8) = 3 + √(-8+9)

= 3 + √1 = 4

let x = 5.67

f(5.67) = -1.8711

f^-1 (-1.8711) = 3 + √(-1.8711+9)

= 3+√7.1289

=3 + 2.67

= 5.67

I am very confident my inverse is correct!

## Answer this Question

## Related Questions

- Calculus Help - The formula C =5/9(F − 32), where F ≥ −459.67...
- Last two CALC questions. :) - 8. If f(x) = sin(7 − 5x), find f′(&#...
- Pre-Calc - Does y=1/x have an inverse? It is a one-to-one function, so it should...
- pre calculus - Find the inverse of the function below. Graph the function below ...
- PRE-CALC - At how many points is this function discontinuous? f(x)=(2(x − ...
- Pre-Calculus - Find the inverse function for the function f(x)=2^(x)+1/2^(x)-1 ...
- Algebra - The function f(x)=x 3 +1 4 x−1 4 is a monotonically increasing ...
- Calculus (Need help) - Not sure how do do this. Please help? Find all values of ...
- Pre-caluclus - I do not know how to solve for y to get the inverse of this ...
- Calculus - Find all values of a and b so that the following function is ...

More Related Questions