Assignment 11

 

1.                  Show how the rules for log(a*b) and log(an) come from rules for exponents.

2.                  Write (1/2)t/350 in terms of the exponential function.

3.                  Assuming monthly compounding, how long does it take money invested at 5% to double?  Repeat for continuous compounding.

4.                  We wish to fit the data below to a curve of the form N = A (1/s)d.  Take the log to get a linear equation for log(N) to fit, and then fit the data to this problem.  Plot the original data, and the fitted curve.

N

s

28

¼

83

1/8

246

1/16

746

1/32

5.                  Solve the following for x.

a.      ln(x2)=3

b.      2x = 104-x

c.      logx(2)=1.5

6.                  pH is defined as –log10(concentration of H+ ions in moles per liter).  If a liquid has pH = 5.3, what is the H+ concentration?

7.                  If f(x) = 3x, what is f-1?  Graph both on the same axes.