Logarithms

<iframe scrolling="no" src="http://www.geogebratube.org/material/iframe/id/39853/width/1456/height/724/border/888888/rc/false/ai/false/sdz/false/smb/false/stb/false/stbh/true/ld/false/sri/false" width="1456px" height="724px" style="border:0px;"> </iframe>