Log of a product is a sum. Log of a quotient is a difference. Log of a power brings the exponent out front. log(ab) = log a + log b. log(a/b) = log a − log b. log(aⁿ) = n log a. Logs as a set are in logarithms.
Expand or condense
The ACT often wants one log turned into two, or two turned into one. Graphing logs is in logs in Desmos.
Change of base is the keypad move, in change of base. The short list is in ACT Math formulas.
The bottom line
Product → add. Quotient → subtract. Power → multiply in front.
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