Matematică
rubei
2015-11-09 14:24:09
x: 2 + 2^2 + 2^3 + ... + 2^2000=4^1000 × x -8^667-2
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pufuliciult
2015-11-09 17:53:37

x/2+2(1+2+...+2^1999)=2^2000 *x-(2³)^667-2 dar (2³)^667=2^2001 atunci x/2+2^2001+2(2^2000-1)/(2-1) +2=2^2000 * x x/2+2^2001+2^2001-2+2=2^2000*x dar 2^2001+2^2001=2^2002 atunci x/2+2^2002=2^2000 x 2^2002=x(2^2000-1/2) 2^2002=x(2^2001 -1)/2 2^2003=x(2^2001-1) x=2^2003/(2^2001-1)

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