Results 1 to 3 of 3

Math Help - Inverse Functions

  1. #1
    Newbie
    Joined
    Apr 2009
    Posts
    8

    Inverse Functions

    I need help with these 3 problems. Please explain so I can know how to do them. I did try some of them

    Find a formula for the inverse of the function.

    26. y=e^x/1+2e^x

    Find the exact value of each expression.

    34. (a) ln(1/e)= -1 I don't if that's right.

    36. (b) ln(ln e^e10)

    Express the given quantity as a single logarithm.

    ln(1+x^2) + 1/2 ln x - ln sin x = ln sq[1+x^2]/ sin x

    THis is my first week of college and it's already hard. I have a quiz tomorrow.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member
    Joined
    Jan 2009
    Posts
    290
    Learn to use latex!

    \ln \frac {1}{e}=-\ln e=-1

    \ln \ln e^{e^{10}}=\ln e^{10}=10

    \frac {1}{2} \ln x=\ln \sqrt x
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor Calculus26's Avatar
    Joined
    Mar 2009
    From
    Florida
    Posts
    1,271
    26

    You want to solve for x --this gives f^-1(y)

    Clear fractions

    y + 2ye^x = e^x

    isolate e^x

    e^x (2y-1) = -y

    e^x = y/(1-2y)

    Take lns

    x= ln[y/(1-2y)]

    f^(-1) (x) = ln[x/(1-2x)]

    34a ln(1/e) = ln(1) - ln(e) I'll let you explain why this is -1

    36 Not clear do you mean ln(ln[e^(10e)]) ?

    For the last problem use the 3 basic prop

    lna + lnb =ln(ab)

    ln(a)-ln(b) = ln(a/b)

    ln(a^r) = rln(a)
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. inverse functions
    Posted in the Algebra Forum
    Replies: 3
    Last Post: November 22nd 2009, 04:58 PM
  2. Replies: 2
    Last Post: October 19th 2009, 02:47 AM
  3. inverse one-one functions
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: September 12th 2009, 04:06 PM
  4. inverse functions
    Posted in the Algebra Forum
    Replies: 2
    Last Post: April 27th 2009, 07:54 AM
  5. Functions and Inverse
    Posted in the Algebra Forum
    Replies: 2
    Last Post: April 16th 2009, 01:16 AM

Search Tags


/mathhelpforum @mathhelpforum