Is 1+x+x^2+x^3+x^4<1/(1-x)? 1) x>0 2) x<1 * A so

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Is 1+x+x^2+x^3+x^4<1/(1-x)? 1) x>0 2) x<1 * A so

by [email protected] Revolution » Mon Mar 21, 2016 3:32 am
Is 1+x+x^2+x^3+x^4<1/(1-x)?

1) x>0
2) x<1

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[Course] Starting $79 for on-demand and$60 for tutoring per hour and $390 only for Live Online. Email to : [email protected] Elite Legendary Member Posts: 3991 Joined: 24 Jul 2015 Location: Las Vegas, USA Thanked: 19 times Followed by:36 members by [email protected] Revolution » Wed Mar 23, 2016 5:42 pm Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution. Is 1+x+x^2+x^3+x^4<1/(1-x)? 1) x>0 2) x<1 The question is (1-x^5)/(1-x)<1/(1-x)? and -x^5/(1-x)<0?, x^5/(x-1)<0? is derived when delete 1/(1-x) from the both equations of 1/(1-x)-x^5/(1-x)<1/(1-x)?. When you multiply (x-1)^2 to the both equations, x^5(x-1)<0? is derived. Divide it with x^4 and it becomes x(x-1)<0?. That is, 0<x<1? is derived, which makes C the answer. Math Revolution The World's Most "Complete" GMAT Math Course! Score an excellent Q49-51 just like 70% of our students. [Free] Full on-demand course (7 days) - 100 hours of video lessons, 490 lesson topics, and 2,000 questions. [Course] Starting$79 for on-demand and $60 for tutoring per hour and$390 only for Live Online.
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