Pre-Calculus - Week 4
Homework
Check each answer individually. Use the hint if you get stuck, then ask the tutor.
Problem 1 · easy
Simplify: 3^4 * 3^(-2).
Problem 2 · easy
Evaluate: 8^(2/3).
Problem 3 · medium
Evaluate: 16^(-3/4).
Problem 4 · easy
Is f(x) = 3^x growth or decay? State domain and range.
Problem 5 · easy
Is f(x) = (0.5)^x growth or decay? State domain and range.
Problem 6 · easy
Evaluate e^0 and e^1 (exact values, then approximate e^1 to 3 decimal places).
Problem 7 · easy
State the horizontal asymptote of f(x) = 5^x.
Problem 8 · easy
Describe the transformation: g(x) = 2^x - 3 relative to f(x) = 2^x.
Problem 9 · easy
State the new HA of g(x) = 2^x - 3.
Problem 10 · medium
Describe: g(x) = e^(x+2) + 1.
Problem 11 · easy
Solve: 3^x = 81.
Problem 12 · easy
Solve: 4^(x-1) = 16.
Problem 13 · medium
Solve: (1/2)^x = 32.
Problem 14 · medium
Solve: 27^x = 9. Express x as a fraction.
Problem 15 · medium
$2000 is invested at 4% compounded quarterly for 10 years. Find A (round to the nearest cent).
Problem 16 · medium
$5000 is invested at 3% continuously compounded for 8 years. Find A (use e^0.24 ≈ 1.2712).
Problem 17 · medium
A radioactive element has half-life 10 years. Starting with 100g, how much remains after 30 years?
Problem 18 · medium
A bacteria colony doubles every 3 hours. Starting with 500 bacteria, how many after 12 hours?
Problem 19 · easy
Find the y-intercept of g(x) = 3 * e^x - 1.
Problem 20 · easy
Solve 2^(3x) = 2^(x+4).
Problem 21 · medium
Which grows faster for large x: f(x) = x^10 or g(x) = 2^x?
Problem 22 · easy
The population of a city is modeled by P(t) = 50000 * e^(0.02t). What is the population at t=0?
Problem 23 · medium
For P(t) = 50000 * e^(0.02t), what is the approximate population after 10 years? (Use e^0.2 ≈ 1.2214)
Problem 24 · medium
Solve: 5^(2x+1) = 125.
Problem 25 · challenge
Compare: which is larger, e^3 or 3^e? (Use e ≈ 2.718, e^3 ≈ 20.09, 3^e ≈ 3^2.718 ≈ 19.81)