Unanswered Questions

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Lê Quốc Trần Anh Coodinator
06/05/2018 at 13:44
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Are there an infinite number of real solutions to $x^6+\sqrt{x^4+4x^3+6x^2+4x+1}=y$? Prove your answer.

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Lê Quốc Trần Anh Coodinator
06/05/2018 at 13:43
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Let $x,y,z$ be integers and $0 < x < y^3$ and $x+y^3=z^3$. Find the least possible value for $y+z$ of all such triples $(x,y,z)$. Prove that your answer is correct.

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Lê Anh Duy
02/05/2018 at 09:57
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15) Given \(\dfrac{a}{c}=\dfrac{a-b}{b-c}\)

Prove that: \(\dfrac{1}{a}+\dfrac{1}{a-b}=\dfrac{1}{b-c}-\dfrac{1}{c}\)

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Lê Quốc Trần Anh Coodinator
01/05/2018 at 02:49
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In a $3\times 4$ grid, Rob starts at $(0,0)$ and needs to reach $(3,4)$ while only moving right or up. Given that he cannot pass through $(2,2)$, how many distinct paths are possible?

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Lê Quốc Trần Anh Coodinator
01/05/2018 at 02:47
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In non-right $\triangle ABC$, $AB=18$ and $AC =x$. $AD$ intersects line segment $BC$ so that $BD=12$ and $DC=15$. Let $AD=y$. Find $\frac{x}{y}$

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Lê Quốc Trần Anh Coodinator
01/05/2018 at 02:46
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Given triangle ABC. AD,BE and CF are the height of the triangle. Point E and F are on line GH where G and H are on the circle. Prove that AG=AH

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Lê Quốc Trần Anh Coodinator
23/04/2018 at 11:01
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In right pyramid PABCD, ABCD is a square with sides of length 2 and the distance from P to the center of square ABCD is 1. A plane intersects the pyramid at A and intersects edges PB, PC and PD at points B', C' and D', respectively. If $B'B/PB=1/4$and $D'D/PD=1/5$, what is the value of the ratio $C'C/PC$? Express your answer as a common fraction.

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Lê Quốc Trần Anh Coodinator
23/04/2018 at 11:00
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Ojns is robbing some gold! He brings a $2.5$ kg briefcase which has volume $25$ cm by $75$ cm by $50$ cm. If he can lift a maximum of $75$ kg, and he plans on filling up the whole case, could he lift it? If not, what is the maximum number of bars of gold, each measuring $3$ cm by $12.5$ cm by $5$ cm, should he put in the case so he can lift it?

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Lê Quốc Trần Anh Coodinator
23/04/2018 at 10:59
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Billy can mow a lawn in 6 hours and paint a roof in 2 hours. Joel can mow a lawn in 8 hours and paint a roof in 4 hours. Elton can mow a lawn in 4 hours and paint a roof in 4 hours.

Billy and Elton begin painting the roof while Joel begins mowing the lawn. When Billy and Elton finish painting the roof, Elton goes inside to play the piano while Billy helps Joel finish mowing the lawn. How long will it take to do both paint the roof and mow the lawn?

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Lê Anh Duy
18/04/2018 at 15:40
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Please don't ask quetions that is so easy like (pls):

- What is area of the square?

- The greatest number 3-digit is : ...

 

     Help me in ten minutes!!