BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

Exponents/Radicals: Simplify ( 1 / 3 - sqrt8 ) ²

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Master | Next Rank: 500 Posts
Posts: 400
Joined: Mon Dec 10, 2007 1:35 pm
Location: London, UK
Thanked: 19 times
GMAT Score:680
by II » Sat Dec 29, 2007 4:49 pm
Simplify:

( 1 / 3-√8 ) ²

A) 9+√8
B) 9+2√8
C) 9+6√8
D) 17+2√8
E) 17+6√8

Can you please let me know how you get to the answer.
Thanks.
II
Last edited by II on Tue Apr 29, 2008 6:34 am, edited 2 times in total.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
Senior | Next Rank: 100 Posts
Posts: 59
Joined: Fri Sep 14, 2007 10:35 am
Thanked: 1 times

by beingAndNothing » Sat Dec 29, 2007 8:14 pm
1/(3-sqrt(8)) = 3+sqrt(8)/(9 - 8) = 3+sqrt(8)

3+sqrt(8) = 9 + 8 + 6sqrt(8) = 17 + 6 sqrt(8)
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 400
Joined: Mon Dec 10, 2007 1:35 pm
Location: London, UK
Thanked: 19 times
GMAT Score:680

by II » Sun Dec 30, 2007 1:19 am
beingAndNothing wrote:1/(3-sqrt(8)) = 3+sqrt(8)/(9 - 8) = 3+sqrt(8)

3+sqrt(8) = 9 + 8 + 6sqrt(8) = 17 + 6 sqrt(8)
can you please explain in more detail ? thanks.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Junior | Next Rank: 30 Posts
Posts: 17
Joined: Mon Dec 17, 2007 9:24 pm
Thanked: 1 times

by starxx68 » Sun Dec 30, 2007 8:05 am
Basically, you square the denominator (3-sqrt(8)) using FOIL, getting 17-6sqrt(8).

Then, you rationalize the denominator by multiplying the whole fraction (1/(3-sqrt(8)) by (17+6sqrt(8))/(17+6sqrt(8)). You find that the denominator gives you 289-288 = 1, so you end up just with (17+6sqrt(8)) in the numerator.

The smiley faces = the number 8. I'm not sure why they become smileys.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Newbie | Next Rank: 10 Posts
Posts: 8
Joined: Wed Sep 14, 2011 9:56 pm

by kanishkporwal » Fri Sep 23, 2011 2:07 am
Still can't figure out how to simplify radicals?
Log on to tutorvista.com for more.


https://math.tutorvista.com/number-syste ... icals.html
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1