1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Algebra 2 natural logarithms problem

  1. Apr 16, 2004 #1
    Problem 51.
    At a constant temperature, the atmospheric pressure p, in pascals, is given by the formula p=101.3e^-0.001h, where h is the altitude in meters. Find h when p is 74.3 pascals. Hint: Start by taking the natural logarithms of the expressions on each side of the equation.

    Solve and check.
    41. (29.3)^4x-1=(17.3)^5x+2
  2. jcsd
  3. Apr 16, 2004 #2
    1. The problem tells you how to solve it. What've you tried?

    2. Manipulate the expression to get a common exponent, and then take the logarithm. What've you tried so far?

  4. Apr 16, 2004 #3
    regard on problem 51.

    So it would be:
    Is this right, so far? If so what is the next step??
  5. Apr 16, 2004 #4


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    What did you do to go through that step?

    a latural logarithm is like "the opposite" of an e^

    If you put them together, you get 1.

    So, take ln of both sides to get rid of the e^-0.001*h, and give you *some number* times -.001h on the right side, and ln(74.3) on the left.
  6. Apr 16, 2004 #5
    What'd you do between the third and fourth line? How'd you make the h disappear? Why wasn't the first step you did taking the natural logarithm of both sides like the problem says?

  7. Apr 16, 2004 #6

    Is this right so far??

    Any given program, when running, is obsolete.
    (Laws of Computer Programming, I)
  8. Apr 16, 2004 #7

    ln(101.3*e^(-.001h)) = ln(101.3) + ln(e^(-.001h)) = ln(101.3) - .001h

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook