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Evaluating an exponential function that models a real-world situation

  • Thread starter Drakkith
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  • #1
Drakkith
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Homework Statement



Suppose that the velocity v(t) (in m/s) of a sky diver falling near the Earth's surface is given by the following exponential function, where time is measured in seconds.

v(t) = 55 (1-e-0.18(t))

Find the initial velocity of the sky diver and the velocity after 6 seconds.
Round your answers to the nearest whole number as necessary.

Homework Equations



None.

The Attempt at a Solution



I don't know what e is, so I can't even attempt this. And it's an online course with no book, just an online program we have to use for everything. It doesn't tell me what e is either.
 

Answers and Replies

  • #2
Dick
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Homework Statement



Suppose that the velocity v(t) (in m/s) of a sky diver falling near the Earth's surface is given by the following exponential function, where time is measured in seconds.

v(t) = 55 (1-e-0.18(t))

Find the initial velocity of the sky diver and the velocity after 6 seconds.
Round your answers to the nearest whole number as necessary.

Homework Equations



None.

The Attempt at a Solution



I don't know what e is, so I can't even attempt this. And it's an online course with no book, just an online program we have to use for everything. It doesn't tell me what e is either.
e is Euler's number. http://en.wikipedia.org/wiki/E_(mathematical_constant)
 
  • #3
Drakkith
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  • #4
Dick
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Thanks. I couldn't even find e in the 'dictionary' part of the program. You'd think they'd give it to you if you have to use it...
Yes, they probably should. Though it's kind of standard.
 
  • #5
SteamKing
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You run into e a lot, especially in connection with natural logs.

d/dx (e^x) = e^x

Integral (e^x) dx = e^x + C

e^(i*pi) + 1 = 0, which relates e, pi, i, 0, and 1 in a single formula [i = SQRT (-1)]
 

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