Identify base and argument: Identify the base of the logarithm and the argument.The base of the logarithm is 27, and the argument is (1)/(243).We need to express both the base and the argument as powers of a common base to simplify the logarithm.
Express as powers of 3: Express the base 27 and the argument 2431 as powers of 3.27 is a power of 3 because 27=33.243 is also a power of 3 because 243=35.Therefore, 270 can be written as 271 since 2431 is the reciprocal of 243.
Rewrite using new expressions: Rewrite the logarithm using the new expressions for the base and the argument. log27(2431) becomes log33(3−5).
Apply logarithm power rule: Apply the logarithm power rule.The power rule of logarithms states that logb(an)=n⋅logb(a).Using this rule, we can simplify log33(3−5) to −5⋅log33(3).
Evaluate log33(3): Evaluate the logarithm log33(3). Since the base of the logarithm (33) and the argument (3) are powers of the same number, we can simplify this further. log33(3) is asking "3 to what power gives 3?" The answer is 1 because 31=3. Therefore, log33(3)=1.
Multiply by −5: Multiply the result from Step 5 by −5.−5×log33(3)=−5×1=−5.This is the value of the original logarithm.