evaluation function: For f(x) = (x-2)/(x+1), find f(x+2), f(1/x)

[mech649]

hello, i am having trouble understanding number 19 a and b.

. . .\(\displaystyle \mbox{Let }\, f(x)\, =\, \dfrac{x\, -\, 2}{x\, +\, 1}.\, \mbox{ Find the following:}\)

. . . . .\(\displaystyle \mbox{(a) }\, f(x\, +\, 2)\)

. . . . .\(\displaystyle \mbox{(a) }\, f\left(\dfrac{1}{x}\right)\)

i replace the x with the number provided but my final answer is totally different from the answers in the book.

 

[Otis]

What answer did you get? Can you show any work?

What is the answer in the book?

 

[Steven G]

hello, i am having trouble understanding number 19 a and b.

. . .\(\displaystyle \mbox{Let }\, f(x)\, =\, \dfrac{x\, -\, 2}{x\, +\, 1}.\, \mbox{ Find the following:}\)

. . . . .\(\displaystyle \mbox{(a) }\, f(x\, +\, 2)\)

. . . . .\(\displaystyle \mbox{(a) }\, f\left(\dfrac{1}{x}\right)\)

i replace the x with the number provided but my final answer is totally different from the answers in the book.

\(\displaystyle f(x) = \dfrac{x-2}{x-1}\) Now rewrite this but put ( ) instead of x.

\(\displaystyle f( ) = \dfrac{( )-2}{( )-1}\).

Now whatever is put in between the parenthesis in f( ) you put the same thing in between the other parenthesis