How do you evaluate log_3 (1/81)?

1 Answer
Oct 18, 2016

By reducing the logarithm using the laws of logs, and reducing the number to a power of the base the result follows. =-4

Explanation:

color(red)(log_"3"(1/81)=log_"3"(1)-log_"3"81)

since

log_a(X/Y)=log_a(X)-log_a(Y)

color(red)(log_"3"(1/81)=0-log_"3"3^4)

since log_a1=0

AAa inRR

color(red)(log_"3"(1/81)=-4log_"3"3)

since log_aX^n=nlog_aX

color(red)(log_"3"(1/81)=-4)

since log_aa=1