Question #f8e12

1 Answer
Dec 4, 2016

x=100e^-13.57~~1.278xx10^-4

Explanation:

We will use the following properties of logarithms and exponents:

  • ln(xy) = ln(x)+ln(y)
  • e^ln(x) = x
  • e^-x = 1/e^x
  • e^(x+y) = e^xe^y

With those:

ln(0.01x) = -13.57

=> ln(0.01)+ln(x) = -13.57

=> ln(x) = -13.57-ln(0.01)

=> e^ln(x) = e^(-13.57-ln(0.01))

:. x = e^(-(13.57+ln(0.01)))

=1/e^(13.57+ln(0.01))

=1/(e^13.57e^ln(0.01))

=1/(0.01e^13.57)

=100e^-13.57~~1.278xx10^-4