tim x dua vao quan he uoc boi:tim so tu nhien x sao cho x-1 la uoc cua 12tim so tu nhien x sao cho 2x+1 la uoc cua 28tim so tu nhien x sao cho x+15 la boi cua x+3tim cac so nguyen x,y sao cho (x+1)(y-2)=3tim so nguyen x sao cho(x+2).(y-1)=2tim so nguyen to x vua la uoc cua 275 vua la uoc cua 180tim so nguyen to x,y biet x+y=12 va UCLL (x:y)=5tim so tu nhien x,y biet x+y=32 va UCLL (x:y)=8tim so tu nhien x biet x chia het cho10; xchia het cho12; x chia het cho15 va 100<x<150tim so x nho nhat khac 0b...
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tim x dua vao quan he uoc boi:
tim so tu nhien x sao cho x-1 la uoc cua 12
tim so tu nhien x sao cho 2x+1 la uoc cua 28
tim so tu nhien x sao cho x+15 la boi cua x+3
tim cac so nguyen x,y sao cho (x+1)(y-2)=3
tim so nguyen x sao cho(x+2).(y-1)=2
tim so nguyen to x vua la uoc cua 275 vua la uoc cua 180
tim so nguyen to x,y biet x+y=12 va UCLL (x:y)=5
tim so tu nhien x,y biet x+y=32 va UCLL (x:y)=8
tim so tu nhien x biet x chia het cho10; xchia het cho12; x chia het cho15 va 100<x<150
tim so x nho nhat khac 0b biet x chia het cho 24 va 30
40 chia het cho x . 56 chia het cho x va x>6
\(\left(x-3\right)^2-x\left|x-3\right|=0^{\left(1\right)}\)
\(\left(1\right)\Rightarrow\left(x-3\right)^2=x\left|x-3\right|^{\left(2\right)}\)
\(\left(x-3\right)^2\ge0,\left(2\right)\Rightarrow x\ge0\left(ĐK\right)\)
\(\left(x-3\right)^2-x\left|x-3\right|=0\)
\(\left(x-3\right)^2=x\left(x-3\right)\)
\(x^2-6x+9=x^2-3x\)
\(-6x+9=-3x\)
\(-6x+3x=-9\)
\(x\left(-6+3\right)=-9\)
\(x.\left(-3\right)=-9\)
\(\Rightarrow x=3\left(tm\right)\)