Processing Math: Done
To print higher-resolution math symbols, click the
Hi-Res Fonts for Printing button on the jsMath control panel.

jsMath

Solution 2.3:1d

From Förberedande kurs i matematik 1

Revision as of 13:02, 20 September 2008 by Ian (Talk | contribs)
Jump to: navigation, search

We apply the standard formula for completing the square,


x2+ax=x+2a22a2 

on our expression and this gives


x2+5x=x+252252=x+252425 

The whole expression becomes


x2+5x+3=x+252425+3=x+252425+412=x+252+41225=x+252413


A quick check shows that we have calculated correctly.


x+252413=x2+225x+252413=x2+5x+425413=x2+5x+412=x2+5x+3