My Math Forum integer part of S

 Algebra Pre-Algebra and Basic Algebra Math Forum

September 22nd, 2012, 07:51 PM   #1
Senior Member

Joined: Apr 2012

Posts: 799
Thanks: 1

integer part of S

[attachment=0:1henah5g]integeral part of S.jpg[/attachment:1henah5g]
Attached Images
 integeral part of S.jpg (6.8 KB, 101 views)

 September 22nd, 2012, 09:22 PM #2 Senior Member     Joined: Jul 2010 From: St. Augustine, FL., U.S.A.'s oldest city Posts: 12,211 Thanks: 520 Math Focus: Calculus/ODEs Re: integer part of S Squaring gives: $S^2=1991+S$ $S^2-S-1991=0$ Hence, taking the positive root, and using the floor function to return the integral portion, we find: $\left\lfloor \frac{1+3\sqrt{885}}{2} \right\rfloor=45$
 September 23rd, 2012, 04:46 AM #3 Math Team     Joined: Mar 2012 From: India, West Bengal Posts: 3,871 Thanks: 86 Math Focus: Number Theory Re: integer part of S If the question is to find the integral part of $\sqrt{1991+\sqrt{1991+\sqrt{1991 . . . + \sqrt{1991}}}}$, then it is impossible to find it. Since we do not know how many times 1991 is nested under the square root sign. The question should be asking to find the integral part of $\underbrace{\sqrt{1991+\sqrt{1991+\sqrt{1991 + . . . }}}}_{\text{infinite times}}$

 Tags integer, part

 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post Jakarta Number Theory 0 May 12th, 2013 11:09 AM Minni04 Geometry 8 March 4th, 2013 01:48 AM Fernando Number Theory 1 April 13th, 2012 07:19 AM haruka-san Advanced Statistics 6 November 28th, 2007 08:29 AM

 Contact - Home - Forums - Cryptocurrency Forum - Top