CASIO

Use – [Func Analysis] > [Logarithm(log)] to input logab as log (a, b). Base 10 is the initial default setting if you do not input anything for a.

Example 1: log101000 = log 1000 = 3

• – [Func Analysis] > [Logarithm(log)] 1000
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Example 2: log216 = 4

• – [Func Analysis] > [Logarithm(log)] 2(,)16
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The key (or – [Func Analysis] > [Logarithm(logab)]) also can be used for input, but only while MathI/MathO or MathI/DecimalO is selected for Input/Output on the SETTINGS menu. In this case, you must input a value for the base.

Example 3: log216 = 4

• 216
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Use (ln) or – [Func Analysis] > [Natural Logarithm] to input "ln".

Example: ln 90 (= loge90) = 4.49980967

• (ln)90
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