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На фото,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
(5/6у-3/5х)^2=25/36у^2-1/2ху+9/25х^2;
^2-это квадрат
(2х-5)^2(х-5) = (2х-5)(х-5)^2
(2х-5)^2(х-5) - (2х-5)(х-5)^2=0
(2x-5)(x-5)((2x-5)-(x-5))=0
(2x-5)(x-5)(2x-5-x+5)=0
(2x-5)(x-5)(x)=0
(x-2.5)(x-5)(x)=0
X1=2.5
X2=5
<span>X3=0</span>
(х+у+2с)(х+у-2с)=(x+y)^2-(2c)^2=x^2+2xy+y^2-4c^2
(а+1)^2(а-1)^2=((а+1)(а-1))^2=(а^2-1)^2=a^4-2a^2+1
2(х+у)+а(-х-у)^2+(х-у)^3=(х+у)(2+a(x+y))+(х-у)^3=(х+у)(2+ax+ay)+(х-у)^3=