How to Solve an Improper Integral Problem

[learningsumth]

Homework Statement

hi, I've been working on this for the past half hour and i can't seem to get the right answer

definite integral from 1 to infinity, dx/[(x)(2x+5)]
[PLAIN]http://www3.wolframalpha.com/Calculate/MSP/MSP558719f9237h7g3ceg5000000h4efg42afe11g4c?MSPStoreType=image/gif&s=27&w=272&h=39

The Attempt at a Solution

i keep getting (2/5)ln(7) as opposed to (1/5)log(7/2) that wolfram gives me.

thanks so much!

 

[LCKurtz]

It's difficult to see what your mistake is if you don't show us your work.

 

[TheoMcCloskey]

Homework Statement

hi, I've been working on this for the past half hour and i can't seem to get the right answer

definite integral from 1 to infinity, dx/[(x)(2x+5)]
[PLAIN]http://www3.wolframalpha.com/Calculate/MSP/MSP558719f9237h7g3ceg5000000h4efg42afe11g4c?MSPStoreType=image/gif&s=27&w=272&h=39

The Attempt at a Solution

i keep getting (2/5)ln(7) as opposed to (1/5)log(7/2) that wolfram gives me.

thanks so much!

LCKurtz - can you show some work so we might be able to find where you went wrong? For example, how did you perform integration?