# search For f - 1

• Oct 28th 2007, 05:46 PM
iceman1
search For f - 1
Hey Guys Hope you are Fine , i need some Help with those numbers i got a lot of them :rolleyes:

determine For f-1

1)f: x --> (radical) x ^ 2 x E R
2) f: x ---> x ^ 2 for x = and > 0
- X ^ 2 <0

3). f: x ---> sinx, x E R

4)f: x ---> x 2 / x-1, x # 1

5)f: x --> x ^ 2-4x 3 / x ^ 2-4x-5, s E] 5 + infinity[

6)Show that the function:
F: x --> x ^ 3-x, x E [1,3] admits a function reciproque

N.B: f-1 ---> http://i22.tinypic.com/2u88mzr.jpg

• Oct 28th 2007, 06:11 PM
Jhevon
Quote:

Originally Posted by iceman1
Hey Guys Hope you are Fine , i need some Help with those numbers i got a lot of them :rolleyes:

determine For f-1

1)f: x --> (radical) x ^ 2 x E R
2) f: x ---> x ^ 2 for x = and > 0
- X ^ 2 <0

3). f: x ---> sinx, x E R

4)f: x ---> x 2 / x-1, x # 1

5)f: x --> x ^ 2-4x 3 / x ^ 2-4x-5, s E] 5 + infinity[

6)Show that the function:
F: x --> x ^ 3-x, x E [1,3] admits a function reciproque

N.B: f-1 ---> http://i22.tinypic.com/2u88mzr.jpg

to find \$\displaystyle f^{-1}(x)\$, if it exists. switch x and y and solve for y

example: if \$\displaystyle f(x) = x + 1\$, find \$\displaystyle f^{-1}(x)\$

since \$\displaystyle y = x + 1\$ for \$\displaystyle f^{-1}(x)\$, switch x and y

we get: \$\displaystyle x = y + 1\$

\$\displaystyle \Rightarrow y = x - 1\$

therefore, \$\displaystyle f^{-1}(x) = x - 1\$

now do the same for your questions