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Applying the Pythagoras' theorem, we deduce that the length of slant is : \(\sqrt{5^2+\left(1.5\right)^2}=\dfrac{\sqrt{109}}{2}\) (inches)
The area which is covered with chocolate is :
\(1,5\pi.\dfrac{\sqrt{109}}{2}=\dfrac{3\pi\sqrt{109}}{4}=24.5993926...\approx24.6\)(square inches)
Lê Quốc Trần Anh selected this answer.
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Every time you move, you need to change by 1. To get from 3-9, you must step through 7 different numbers (from 3 to 9). If you deduce 3-2-1-... you won't make to 9.
So there are 7 different numbers.
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manhmiio 14/09/2017 at 22:01
l do not know english,notvery clear
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Consider 4 cases :
+ n = 0 => n4 - n + 2 = 2 (unsatisfied)
+ n = 1 => n4 - n + 2 = 2 (unsatisfied)
+ n = 2 => n4 - n + 2 = 16 = 42 (satisfied)
+ n > 2
\(\circledast n^4-n+2< n^4\)
\(\circledast\left(n^4-n+2\right)-\left(n^2-1\right)^2=n^4-n+2-n^4+2n^2-1\)
\(=2n^2-n+1=2\left(n^2-\dfrac{1}{2}n+\dfrac{1}{2}\right)\)
\(=2\left(n^2-2n.\dfrac{1}{4}+\dfrac{1}{16}+\dfrac{7}{16}\right)=2\left(n-\dfrac{1}{4}\right)^2+\dfrac{7}{8}>0\)
\(\Rightarrow\left(n^2-1\right)^2< n^4-n+2\)
Hence, n4 - n + 2 is between two consecutive perfect squares : (n2 - 1)2 and (n2)2, so n4 - n + 2 is not a perfect square
So, n = 2
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Ngô Tấn Đạt 15/10/2017 at 12:05
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Let a be the original price of the shirt. We have :
\(\left(1+5\%\right).\left(1-20\%\right)a=15.54\Leftrightarrow105\%.80\%a=15.54\) \(\Leftrightarrow a=18.5\)
So, the answer is $18.50
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Because 2017 is a prime number
=> \(F\left(2017\right)=1;2017\)
So their sum is: \(1+2017=2018\)
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\(n^5-n+2=n\left(n^4-1\right)+2=n\left(n^2+1\right)\left(n^2-1\right)+2\)
\(=n\left(n-1\right)\left(n+1\right)\left(n^2+1\right)+2\)
We see: \(\left(n-1\right)\cdot n\cdot\left(n+1\right)⋮3\) (is product of 3 consecutive natural numbers)
\(\Rightarrow n^5-n+2\equiv2\left(mod3\right)\)
But no square numbers are in the form 3k + 2
So \(n\notin\varnothing\)
Lê Quốc Trần Anh selected this answer.
Lê Quốc Trần Anh Coordinator
08/07/2018 at 06:19
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Tôn Thất Khắc Trịnh 25/07/2018 at 06:52
Applying the triangular inequality:
\(12-5< n< 12+5\)
\(\Leftrightarrow7< n< 17\)
So n varies from 8 to 16, therefore there are 9 possible integer values of n
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Cristiano Ronaldo 03/08/2018 at 14:30
Blue, red, yellow, yellow
The solitary paradise lying alone.
What is the quiz?Answer: It's a rainbow