Recent content by lhuyvn

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    Undergrad Divisibility by 11 in Number Theory

    Hi there, I found that we could deduce as following. 3x+7y =0 (mod 11) <=> 8x+4y=0 (mod 11) <=> 4x+2y=0 (mod 11) <=>4x-9y=0 (mod 11) So the answer is D Thank so much for all your help,
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    Undergrad Divisibility by 11 in Number Theory

    Hi again, how about the below problem, please give me advice. Let x and y be possitive integers such that 3x+7y is divisible by 11. Which of the following must also be divisible by 11 A. 4x+6y B. x+y=5 C. 9x+4y D .4x-9y E. x+y-1
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    Graduate Solve Derivative Problem: Lim {P(x+3h)+P(x-3h)-2P(x)}/h^2

    Thank you, arildno It couldn't be more wonderful solutions.
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    Graduate Solve Derivative Problem: Lim {P(x+3h)+P(x-3h)-2P(x)}/h^2

    Hi members, Could anyone help me with the problem following? If x is a real number and P is a polynomial function, then lim {P(x+3h)+P(x-3h)-2P(x)}/h^2 h->0 A)0 B)6P'(x) C)3P''(x) D)9P''(x) E) 00 I guess D should be the answer, I need an explanation. Thank You
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    Undergrad What Is the Probability of Rolling a Six 70 Times in 360 Dice Tosses?

    Hi All, With the given problem below, any suggestion? A fair die is tossed 360 times. The probability that a six comes up on 70 or more of the tosses is A. greater than 0.50 B.between 0.16 and 0.50 C.between 0.02 and 0.16 D.between 0.01 and 0.02 E. less than 0.01
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    Graduate Solving Abstract Algebra Problem: 3 Elements of {p,p+q,pq, p^q,q^p}

    Hi again, I'm preparing for GRE Math. I regconize that Abstract Algebra is the most tough. Here is one of its problem, Any suggestion!. Thank you in advance. Let p and q be distinct primes. There is a proper subgroup J of the additive group of integers which contains exactly three...
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    Graduate What is the maximum value of b for a given function with certain properties?

    Oh, It is so wonderful suggestion ! So, it is solved. The correct answer is D (12)
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    Graduate What is the maximum value of b for a given function with certain properties?

    Hi All, I have a problem, and it is so confusing to me. I put it here in the hope of getting some helps to make it clear. Thank you, the problem is given below. What is the greatest value of b for which any real valued function f that satisfies the following properties mus also...
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    High School What is the probability of winning a game based on coin tosses?

    Thank All for very nice answers !
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    High School Find the Probability of Winning a Coin Toss Game | GRE Math Practice

    Hi members, I have traveled this forum sometimes, But this is my first question. I hope to get your help so that I can prepare better for my GRE Math test. Following is my question. In a game two players take turns tossing a fair coin; the winner is the firt one to toss a head. The...
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    High School What is the probability of winning a game based on coin tosses?

    Hi members, I have traveled this forum sometimes, But this is my first question. I hope to get your help so that I can prepare better for my GRE Math test. Following is my question. In a game two players take turns tossing a fair coin; the winner is the firt one to toss a head. The...