How is this logx=4 done?

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Answer 1 · 2016-09-10T21:09:00

$x = 10, 000$ $x = 10,000$

If no base of the log is shown, it means it is 10.

Log form and exponential form are interchangeable.

${log}_{a} b = c \Leftrightarrow a^{c} = b$ $log_a b = c " "hArr " "a^c = b$

"The base stays the same and the other two change around"

In this case, change the log form to index form:

${log}_{10} x = 4 \Leftrightarrow 10^{4} = x$ $log_10 x = 4 " "hArr " " 10^4 = x$

$x = 10, 000$ $x = 10,000$