x²+(p+2)*x+2p=0
√D=√((p+2)²-4*2p)=√(p²+4x+4-8x)=√(p²-4x+4)=√(p-2)²=p-2.
x₁=(-(p+2)+(p-2))/2=(-p-2+p-2)/2=-4/2=-2.
x₂=(-(p+2)-(p-2))/2=(-p-2-p+2)/2=-2p/2=-p.
Ответ: x₁=-4 x₂=-p.
1. 85:100*15=12.кг 750г
2.132р
3.19 мин
(m-n)^2+m(6n-m)=m^2-2mn+n^2+6mn-m^2=4mn+n^2=4*¼*(-1)+(-1)^2=-1+1=0
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