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什么是对数（续）
以 $10$ 为底的对数是如何定义的？
1. What a logarithm is
What a logarithm is
2. Summary
Summary
3. Changing base to e
For what k does 3^t equal e^(kt) for every t?
4. Solving e-to-the-t equals one tenth
Solve e^t = 1/10. What is t, to two decimal places?
5. Solving a log equals minus one third
Solve ln(t) = -1/3. What is t, to three decimal places?
6. Solving an exponent with a coefficient
Solve e^(1-3t) = 4. What is t, to three decimal places?
7. An equation with no solution
What happens when solving 4 + 3e^(2t) = 2?
8. An exponential can never reach a negative value
The equation e^(2t) = -2/3 has no real solution.
9. Solving a log with a linear argument
Solve ln(5 - 6t) = -2. What is t, to three decimal places?
10. Inverses of shifted and scaled exponentials
For h(x) = 2e^x + 1, what are the inverse's formula and domain?