1.Amplificati raportul algebric x+√7/x-√7 cu x+√7
2.Simplificati raportul algebric pina la un raport ireductibil a^2-2ab+b^2/a^2-b^2
3.efectuati 5/x-2y - 3/x+2y
4.efectuati xy^2/x+y * (x+y)^2/xy
6.2-x/3x+12 : x^2-4/4x+x^2

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Răspunsuri

2014-04-17T22:30:07+03:00
1)=(x+√7)(x+√7)/(x-√7)+(x+√7)=(x²+2√7x+7)/x²-7
2)=(a-b)(a-b)/(a-b)(a+b) simplificam=(a-b)(a+b)
3) aducem la acelasi numitor=[5(x+2y)-3(x-2y)]/(x-2y)(x+2Y)=[5x+10y-3x+6y]/(x²-4y²)=(2x+16y)/(x²-4y²)=2(x+4y)/(x²-4y²)
4)=xy²(x+y)²/xy(x+y) simplificam cu x si y⇒y(x+y)(x+y)/(x+y)=simplificam=y(x+y)
6) =(2-x)(4x+x²)/(3x+12)(x²-4)=(2-x)x(4+x)/3(x+4)(x-2)(x+2) simplificam xu x+4⇒
x(2-x)/3(x-2)(x+2)=-x(x-2)/(x-2)(x+2) simplificam=3x/(x+2)
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