Natural Logarithms
Word Problems
Logarithms
Exponents
Inverses/Composition
100

Evaluate: - ln 1

0

100

One isotope of chromium has a half-life of 23 hours. How long does it take 50 g to decay to 40 g?

7.4 hours

100

Evaluate log28√(2)

 7/2

100

Solve: (y+1)2/3 = 9

26
100

If f(x) = x2 and g(x) = 1-2x find: g(f(x))

1-2x2

200

Evaluate: ln 1/(3√(e^2))

-2/3

200

How much will a $4000 investment be worth after 5 years if it is invested at 8% interest compounded quarterly?

$5943.79

200

Solve: log8x = -1/3

1/2

200

Simplify: 8√(2) / 2√(8)

2√(2)

200

If f(x) = x2 and g(x) = 1-2x find: f(g(x))

(1-2x)2

300

Solve: ln x + ln 3 = ln (x+4)

x = 2

300

How long does it take an investment to double in value if it is invested at 12 % compounded monthly? 

5 years 10 months

300

Express in terms of log4A and log4B: log4(A2/√(B))

2 log4A - 1/2 log4B

300

Solve: 27x+1 = 81

1/3

300

If g(x) = 1-2x find g-1(x)

g-1(x) = (1-x)/2

400

Solve: 3e2x + 2 = 50

x = ln 4

400

The population of a certain type of bacteria doubles every 10 hours. How long will it take the population to triple?

15.8 hours

400

Solve: logax + loga(2x+3) = loga2

1/2

400

Solve: (1/10)y = 100y+3

-2

400

Determine if h(x) = x4-1 has an inverse and find the inverse if it exists.

No inverse, it doesn't pass the horizontal line test. 

500

3e2x -12ex+ 12 = 0

x = ln 2

500

A colony of bacteria has 6.5 x 106 members at 8AM and 9.75 x 106 members at 10:30AM. Find its population at noon.

1.24 x 107 members

500

log3(x+2) + log36 = 3

5/2

500

Solve: 5- 6=0

0

500

Let f(x) = mx + b. For what values of m and b will f(x) = f-1(x)?

m = 1, b = 0