From: Andrew Lorimer <andrew@lorimer.id.au>
Date: Thu, 13 Sep 2018 00:40:59 +0000 (+1000)
Subject: logarithmic inequalities
X-Git-Tag: yr11~37
X-Git-Url: https://git.lorimer.id.au/notes.git/diff_plain/83ce4f9b215d242edc7e167412a8c754f734e2b6

logarithmic inequalities
---

diff --git a/methods/stuff.md b/methods/stuff.md
index 1eb560c..addaf9b 100644
--- a/methods/stuff.md
+++ b/methods/stuff.md
@@ -15,3 +15,12 @@ $^n\sqrt{x}=x^{1/n}$
 ## Logarithms
 
 $$\log_b (x) = n \quad \operatorname{where} \hspace{0.5em} b^n=x$$
+
+## Using logs to solve index eq's
+
+Used for equations without common base exponent
+
+Or change base:  
+$$\log_b c = {{\log_a c} \over {\log_a b}}$$
+
+If $a<1, \quad \log_{b} a < 0$ (flip inequality operator)
\ No newline at end of file