My Math Forum  

Go Back   My Math Forum > High School Math Forum > Algebra

Algebra Pre-Algebra and Basic Algebra Math Forum


Reply
 
LinkBack Thread Tools Display Modes
October 1st, 2007, 12:52 PM   #1
Newbie
 
Joined: Oct 2007

Posts: 3
Thanks: 0

Yes, this may be an easy question, but im stumped

ok, so i've just entered college after taking a year off after high school. So I have COMPLETELY lost all my math skills.....so if you could run me throught the process of how to complete this question, it should clear up some of the others. Thanks!

Simplify:

(3/x) + [1/(x^2 + x)]
----------------------------
(1/x+1) - (1/x-1)

The answer in the book is :
(3x+4)(x-1)
--------------
-2x
rwgturner is offline  
 
October 1st, 2007, 03:35 PM   #2
Senior Member
 
Compendium's Avatar
 
Joined: Sep 2007
From: USA

Posts: 349
Thanks: 67

Math Focus: Calculus
For the denominator, do you mean 1/(x + 1) - 1/(x - 1) or 1/x + 1 - 1/x + 1?
Compendium is offline  
October 1st, 2007, 03:37 PM   #3
Newbie
 
Joined: Oct 2007

Posts: 3
Thanks: 0

1/(x + 1) - 1/(x - 1)

sorry for the confusion
rwgturner is offline  
October 1st, 2007, 04:02 PM   #4
Senior Member
 
Compendium's Avatar
 
Joined: Sep 2007
From: USA

Posts: 349
Thanks: 67

Math Focus: Calculus
What I would do is multiply the numerator and the denominator by (x+1)(x-1), which would eliminate the fractions in the denominator. Then you can simplify the numerator.
Compendium is offline  
October 1st, 2007, 04:15 PM   #5
Newbie
 
Joined: Oct 2007

Posts: 3
Thanks: 0

i still dont understand how you can just multiply both denominator and numerator. both the numerator and denominator are fractions, so i dont understand how the process works.
rwgturner is offline  
October 1st, 2007, 04:32 PM   #6
Senior Member
 
Compendium's Avatar
 
Joined: Sep 2007
From: USA

Posts: 349
Thanks: 67

Math Focus: Calculus
Doing this is multiplying by 1, because (x+1)(x-1)/[(x+1)(x-1)]=1. For the numerator, you distribute (x+1)(x-1) across the terms. You do the same for the denominator.

[3/x + 1/(x(x+1))](x+1)(x-1)
-----------------------------------
[1/(x+1) - 1/(x-1)](x+1)(x-1)


3(x+1)(x-1)/x + (x-1)/x
-------------------------------
(x-1) - (x+1)


(3x^2+x-4)
----------------
-2x


(3x+4)(x-1)
--------------
-2x
Compendium is offline  
Reply

  My Math Forum > High School Math Forum > Algebra

Tags
easy, question, stumped



Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Hopefully a v. easy question... rebell1on Algebra 3 February 8th, 2013 05:07 PM
Very easy question but I can't see it. perla Algebra 2 August 27th, 2011 01:43 PM
Easy question studentx Abstract Algebra 2 December 8th, 2010 05:13 AM
easy question football Algebra 1 April 11th, 2010 04:51 AM
easy question wannabe1 Advanced Statistics 4 March 21st, 2010 04:41 PM





Copyright © 2019 My Math Forum. All rights reserved.