Integration E(y^2)

rbcc

Junior Member
Joined
Nov 18, 2009
Messages
126
HI,

I'm haveing trouble with this question can some one check this over?

\(\displaystyle \int^{a+b}_{a-b} y^{2} \frac{1}{2b} \dy\)dy\displaystyle dy
.
13y312b]aba+b\displaystyle \frac{1}{3}y^{3} \frac{1}{2b}]_{a-b}^{a+b}

a3+3a2b+3ab2+b3a3+3a2b3ab2+b23\displaystyle \frac {a^{3}+3a^{2}b+3ab^{2}+b^{3}-a^{3}+3a^{2}b-3ab^{2}+b^{2}}{3}...12b\displaystyle \frac{1}{2b}
.
6a2b+b33\displaystyle \frac {6a^{2}b+b^{3}}{3}...12b\displaystyle \frac{1}{2b}
.
6a2b+b36b\displaystyle \frac {6a^{2}b+b^{3}}{6b}
.
a2+b26\displaystyle a^{2}+\frac {b^{2}}{6}

thanks!
 
You almost have it. It should be a2+b23\displaystyle a^{2}+\frac{b^{2}}{\boxed{3}}
 
See my attachment.\displaystyle See \ my \ attachment.


[attachment=0:65ezzxie]SCREEN01.JPG[/attachment:65ezzxie]
 

Attachments

  • SCREEN01.JPG
    SCREEN01.JPG
    30.7 KB · Views: 121
Top