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100 points for $49 worth of Veritas practice GMATs FREE VERITAS PRACTICE GMAT EXAMS Earn 10 Points Per Post Earn 10 Points Per Thanks Earn 10 Points Per Upvote If a and b are negative integers, which of the . . . . tagged by: Vincen This topic has 2 expert replies and 0 member replies Top Member If a and b are negative integers, which of the . . . . If a and b are negative integers, which of the following statements must be true? I. (-a)^b is positive. II. (-a)^(-b) is positive. III. a^(-b) is positive. A. None B. II only C. I and II only D. I and III only E. I, II and III The OA is the option C. How can I verify which options are true? Experts, can you help me here? Please. GMAT/MBA Expert GMAT Instructor Joined 04 Oct 2017 Posted: 551 messages Followed by: 11 members Upvotes: 180 Hello Vincen. Let's take a look at your question. If we choose a = -2 and b = -3, we will have I. (-a)^b = (2)^(-3) = 1/(2^3) --> Positive II. (-a)^(-b) = 2^3 --> Positive III. a^(-b) = -2^3 --> Negative Then, the correct answer is the option C. I hope this answer can help you to understand. I'm available if you'd like a follow-up. Regards. _________________ GMAT Prep From The Economist We offer 70+ point score improvement money back guarantee. Our average student improves 98 points. Free 7-Day Test Prep with Economist GMAT Tutor - Receive free access to the top-rated GMAT prep course including a 1-on-1 strategy session, 2 full-length tests, and 5 ask-a-tutor messages. Get started now. GMAT/MBA Expert GMAT Instructor Joined 09 Apr 2015 Posted: 1465 messages Followed by: 19 members Upvotes: 39 Vincen wrote: If a and b are negative integers, which of the following statements must be true? I. (-a)^b is positive. II. (-a)^(-b) is positive. III. a^(-b) is positive. A. None B. II only C. I and II only D. I and III only E. I, II and III We can say a = -2, and b = -1. I. (-a)^b = (-(-2))^-1 = 2^-1 = 1/2 Thus, (-a)^b is positive. II.(-a)^(-b) = (-(-2))^(-(-1)) = 2^1 = 2 Thus, (-a)^(-b) is positive. III. a^(-b) = -2^-(-1) = -2^1 = -2 Thus, a^(-b) IS NOT positive. Answer: C _________________ Jeffrey Miller Head of GMAT Instruction jeff@targettestprep.com See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews • Free Veritas GMAT Class Experience Lesson 1 Live Free Available with Beat the GMAT members only code • 5-Day Free Trial 5-day free, full-access trial TTP Quant Available with Beat the GMAT members only code • FREE GMAT Exam Know how you'd score today for$0

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