How do you solve 2logx=14?

1 Answer
Nov 27, 2015

x=1100 or x=1e2 depending on whether log refers to log10 or loge.

Explanation:

We will use the following:

  • loga(a)=1

  • log(ax)=xlog(a)

  • aloga(x)=x


2log(x)=14=22

log2(2log(x))=log2(22)

log(x)log2(2)=2log2(2)

log(x)=2

(Depending on the context, log may refer to log10 or loge. We will show both cases.)

10log10(x)=102 or eloge(x)=e2

x=102=1100 or x=e2=1e2