Find the exact solution to: ln(x) + ln(7) = ln(21)
Log rules:
log(a) + log(b) = log(ab)
so, in this case, we must find x such that 7x = 21
thus x = 3
similarly, log(a) - log(b) = log(a/b)
rearranging the original equation we get:
ln(x) = ln(21) - ln(7)
so x = 21/7 = 3
BP
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