log 15 base 4 = x find x to 3 dp (with working please. thanks so much)
logbase4(15) = x
by definition of logs 15 = 4^x
take log base 10 of both sides
log 15 = log(4^x)
log 15 = x log 4
x = log 15/log 4 = 1.95344 ~ 1.953
Use base change formula.
\(\log_415 = x\\ x = \dfrac{\ln 15}{\ln 4} \approx 1.953\)
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