imadummy wrote:From a Veritas Prep workbook:
For how many integers, n, does 2^n = n^2
A. Zero
B. One
C. Two
D. Four
E. Eight
yeah, this problem is somewhat unappetizing, as trial and error is the only way to solve it.
this problem strikes me as something unlikely to show up on the gmat, because of its combination of the following 2 factors:
1, soluble only by trial and error;
2, technically an infinity of trials to do (although it becomes perfectly clear after trying x = 3, 4, 5 that no bigger numbers will work).
1) this is not to say that the gmat will
never feature a trial-and-error problem, because of course it often does. however, if there
is a problem based on trial and error, then it will almost certainly feature a finite set of 'trials', usually based on some sort of combinatorial issue.
here is an example from another forum (i don't normally like to cross-post, but i don't recall any equally juicy examples i've posted here).
2) and of course there are problems that would feature an infinity of trials were they to be solved by trial and error - but these problems are usually soluble with some sort of theory / number properties / something else that obviates the need for trial-and-error in the first place.
Last edited by
lunarpower on Sat May 24, 2008 2:51 am, edited 1 time in total.
Ron has been teaching various standardized tests for 20 years.
--
Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
--
Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
--
Learn more about ron