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Jim should receive 3/8 of the proceeds.
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Slice the number XII = 12 across the middle to get VII = 7.
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In base 2, 1 + 1 = 10
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Where is "d"?
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We have: \(y^2=x\left(x+1\right)\left(x+2\right)\left(x+3\right)\)
\(\Leftrightarrow y^2+1=x\left(x+1\right)\left(x+2\right)\left(x+3\right)+1\)
\(\Leftrightarrow y^2+1=\left(x^2+3x+1\right)^2\)
\(\Rightarrow y=0\) (Because \(y^2\) and \(\left(x^2+3x+1\right)^2\) is two consecutive square numbers)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x+1=0\\x+2=0\\x+3=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=-1\\x=-2\\x=-3\end{matrix}\right.\)
So x=0; x=-1; x=-2; x=-3.
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When n has three digits, we have:
\(n+S\left(n\right)\le999+27=1026\) (!)
\(\Rightarrow\) n has four digits.
Now we have:
\(\left(1000a+100b+10c+d\right)+\left(a+b+c+d\right)=1982\)
\(\Leftrightarrow1001a+101b+11c+2d=1982\) (1)
\(\Rightarrow a=\left[\dfrac{1982}{1001}\right]=1\)
\(\left(1\right)\Leftrightarrow101b+11c+2d=981\) (2)
\(\Rightarrow b=\left[\dfrac{981}{101}\right]=9\)
\(\left(2\right)\Leftrightarrow11c+2d=72\) (3)
\(\Rightarrow c=\left[\dfrac{72}{11}\right]=6\)
\(\left(3\right)\Leftrightarrow2d=6\Leftrightarrow d=3\)
Because the factoring is only one
So a=1; b=9; c=6; d=3.
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Condition: \(x\ge82\)
We have: \(\sqrt{x+7}-\sqrt{x-82}=x-2017\)
\(\Leftrightarrow\left(\sqrt{x+7}-45\right)+\left(44-\sqrt{x-82}\right)+2018-x=0\)
\(\Leftrightarrow\dfrac{x-2018}{\sqrt{x+7}+45}+\dfrac{2018-x}{\sqrt{x-82}+44}+2018-x=0\)
\(\Leftrightarrow\left(2018-x\right)\left(\dfrac{1}{\sqrt{x-82}+44}-\dfrac{1}{\sqrt{x+7}+45}+1\right)=0\)
\(x\ge82\Rightarrow1>\dfrac{1}{\sqrt{x+7}+45}>\dfrac{1}{\sqrt{x-82}+44}>0\Rightarrow\dfrac{1}{\sqrt{x-82}+44}+1-\dfrac{1}{\sqrt{x+7}+45}>0\)
\(\Rightarrow2018-x=0\Rightarrow x=2018\)
So \(x=2018\).
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abc is different 0 \(\Rightarrow\) a, b, c is different 0.
We have: \(\dfrac{x-b-c}{a}+\dfrac{x-a-c}{b}+\dfrac{x-a-b}{c}=3\)
\(\Leftrightarrow\left(\dfrac{x-b-c}{a}-1\right)+\left(\dfrac{x-a-c}{b}-1\right)+\left(\dfrac{x-a-b}{c}-1\right)=0\)
\(\Leftrightarrow\dfrac{x-a-b-c}{a}+\dfrac{x-a-b-c}{b}+\dfrac{x-a-b-c}{c}=0\)
\(\Leftrightarrow\left(x-a-b-c\right)\left(\dfrac{1}{a}+\dfrac{1}{b}+\dfrac{1}{c}\right)=0\)
\(\Leftrightarrow x-a-b-c=0\) (because \(\dfrac{1}{a}+\dfrac{1}{b}+\dfrac{1}{c}\ne0\))
\(\Leftrightarrow x=a+b+c\)
So \(x=a+b+c\)
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We have: \(P=10a^2+10b^2+c^2\)
\(=\left(8a^2+\dfrac{1}{2}c^2\right)+\left(8b^2+\dfrac{1}{2}c^2\right)+\left(2a^2+2b^2\right)\)
\(\ge2\sqrt{8a^2.\dfrac{1}{2}c^2}+2\sqrt{8b^2.\dfrac{1}{2}c^2}+4\sqrt{a^2b^2}\) (AM-GM inequality)
\(=4ac+4bc+4ab\)
\(=4\left(ab+bc+ca\right)=4\)
So the minimum of P is 4 when \(a=b=\dfrac{1}{3};c=\dfrac{4}{3}\).
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\(1000000!:999999!=\left(1.2.3.....1000000\right):\left(1.2.3.....999999\right)=1000000\)
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We have: \(x^2\) is a square number
\(\Rightarrow x\in Z\)
-C1: \(x⋮3\)
\(\Rightarrow x^2\equiv0\) (mod 3)
\(\Rightarrow x^2+5\equiv2\) (mod 3) (Impossible because \(x^2+5\) is a square number)
-C2: \(x⋮̸3\)
\(\Rightarrow x^2\equiv1\) (mod 3)
\(\Rightarrow x^2-5\equiv2\) (mod 3) (Impossible because \(x^2-5\) is a square number)
So can't find x.
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\(\sqrt{2.3.4.5.6.7.10}=\sqrt{50400}=60\sqrt{14}\)
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\(5-5.5+5:5=5-25+1=-19\)
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1: \(12.37+12.7+12.6\)
\(=444+84+72\)
\(=600\)
2: \(12.37+12.7+12.6\)
\(=12\left(37+7+6\right)\)
\(=12.50\)
\(=600\).
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We have: \(y^2=\left(y+2018\right)^2\)
\(\Leftrightarrow\left(y+2018\right)^2-y^2=0\)
\(\Leftrightarrow2018\left(2y+2018\right)=0\)
\(\Leftrightarrow2y=-2018\)
\(\Leftrightarrow y=-1009\)
So \(y=-1009\).
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We have: \(A=2018^2-2017^2+2016^2-2015^2+...+2^2-1^2\)
\(=\left(2018-2017\right)\left(2018+2017\right)+\left(2016-2015\right)\left(2016+2015\right)+...+\left(2-1\right)\left(2+1\right)\)
\(=2018+2017+2016+2015+...+2+1\)
\(=\dfrac{2018.2019}{2}=2037171\).
So the last two digits of A is 71.