Vizex Posted May 12, 2006 Share Posted May 12, 2006 So I'm doing some tests corrections for a couple of points in my PreCalc class (Junior in Highschool). The problem below is a limit. I got x=(1/2). My math teacher took a point off. WHY? I can't figure it out, I've done it twice now, and I still get the same answer. Anyone know the right answer? Thanks!! Link to comment Share on other sites More sharing options...
Chadwick Posted May 12, 2006 Share Posted May 12, 2006 the answer is 1. the top goes to a very small number, just the bottom approaches 0, which means you are dividing the numerator by the same number in the denominator. btw wrong forum Link to comment Share on other sites More sharing options...
dreamz Veteran Posted May 12, 2006 Veteran Share Posted May 12, 2006 moved here the answer is NOT 1. when you substitute x = 0, you get 0/0. that's NOT 1. to solve this easily, use l'hopital's rule. differentiate the top and the bottom, then substitute. you'll see it's not 1/2. solve it again. and check your signs. ;) Link to comment Share on other sites More sharing options...
Express Posted May 12, 2006 Share Posted May 12, 2006 -1/2 according to Encarta student 2006 graphing calulator. Link to comment Share on other sites More sharing options...
Mathiasdm Posted May 13, 2006 Share Posted May 13, 2006 moved here the answer is NOT 1. when you substitute x = 0, you get 0/0. that's NOT 1. to solve this easily, use l'hopital's rule. differentiate the top and the bottom, then substitute. you'll see it's not 1/2. solve it again. and check your signs. ;) Correct :) I'm guessing the poster forget a '-'. Link to comment Share on other sites More sharing options...
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