How do you solve $log_10 4+log_10 25$ ?

Question

10527 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-01-24T08:54:22

$log_10 4 + log_10 25 = 2$

If $a, b, c > 0$ then:

$log_c(c) = 1$

$log_c(a) + log_c(b) = log_c(ab)$

$log_c(a^b) = b log_c(a)$

So we find:

$log_10(4) + log_10(25)$

$=log_10(4 * 25)$

$=log_10(100)$

$=log_10(10^2)$

$=2 log_10(10)$

$=2$

How do you solve log_10 4+log_10 25log_10 4+log_10 25?