Troulbe with a rational expression. Yar.

Avaviel

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Joined
Feb 25, 2009
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2
Step 1:
[(1)/(2y-3)]-[(18y)/(8y^3-27)]

Step 2:
[(8y^3-27)/(2y-3)]-[(18y)(2y-3)/(8y^3-27)(2y-3)]

Step 3:
[(8y^3-36y^2+54y-27)]/[(8y^3-27)(2y-3)]

Step 4:
????

Step 5:
World Domination.

So... I have this problem from my College Algebra and Trig class... mostly review right now, but I don't remember anything that caused me this much trouble in Algebra before this. Well, what I DO remember causing me trouble is factoring... and that is where my issue is now. I thought that this involved a Difference of Two Cubes, and I've been trying to factor this like that... but no joy. I've even seperate the numbers into their factors so I could see it, but I can't. So, I think it needs to be factored another way. Can you point me in the right direction?

I can solve the rest of the problem once I factor this part: (8y^3-36y^2+54y-27). My calculator (A voyage 200, great stuff... I don't like it being able to factor that while I can't!) says that it is (2y-3)^3.

Anyway, thanks for the help, and I'll move on doing other problems...
 
I'm so stupid! I had to factor the bottom part too... I'll post the answer once I got it... Why do I always figure it out once I've posted for help?
 
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