6

Set 2: Exponential Functions (Intermediate)

Explanation

Answer: A

Solve: ln(x2)=3\ln(x-2) = 3

A.

x=e3+222.09x = e^3 + 2 \approx 22.09

✓ Correct
B.

x=5x = 5

C.

x=e3218.09x = e^3 - 2 \approx 18.09

D.

x=3x = 3

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Use the definition of natural logarithm. 1. Given: ln(x2)=3\ln(x-2) = 3. 2. Convert: x2=e3x - 2 = e^3. 3. Solve: x=e3+220.09+2=22.09x = e^3 + 2 \approx 20.09 + 2 = 22.09. Strategic Tip: ln(a)=b\ln(a) = b means a=eba = e^b. Choice B is incorrect because ln(3)3\ln(3) \neq 3. Choice C is incorrect because we add 2, not subtract. Choice D is incorrect because ln(1)=03\ln(1) = 0 \neq 3.

Key Steps:

The correct answer is x=e3+222.09x = e^3 + 2 \approx 22.09

Why others are wrong:
B: Choice B is incorrect and may result from a calculation error.
C: Choice C is incorrect and may result from a calculation error.
D: Choice D is incorrect and may result from a calculation error.

🎯 Keep Practicing!

Master all sections for your best SAT score