Given: ln 5 = 1,61 and ln 2 = 0,69

Question

Without the use of a calculator, determine ln100.

Answer 1

ln(5) = 1.61, so e^1.61 = 5

ln(2) = 0.69, so e^0.69 = 2

5²·2² = 100

(e^1.61)²·(e^0.69)² = 100

e^3.22·e^1.38 = 100

e^4.6 = 100

ln(e^4.6) = ln(100)

4.6 = ln(100)

Answer 2

ln 5 = 1.61 → ln 25 = 3.22

ln 2 = 0.69 → ln 4 = 1.38

ln 100 = ln (25 · 4)

ln (25 · 4) = ln 25 + ln 4

What is the next line?