Paper 1 · Indices and Logs
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Lesson 5 of 8
Indices and Logs 5 – Unknown in the power/ the natural log
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- Solve aˣ = b by taking logs of both sides and bringing x down: x = ln(b)/ln(a)
- Use the natural log ln = loge, Euler's number e, and the identity ln(e) = 1
- Isolate the exponential term first: 14·(2ˣ) = 12 becomes 2ˣ = 6/7, THEN take logs
- Solve e-based equations like e^(2x+4) = 12, correct to 2 decimal places
Most recent exam questions
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