[tex]a)~~(-x^{2}+3x) ^{2} =(3x-x^{2}) ^{2}=(3x)^{2} -2\cdot 3x \cdot x^{2} +(x^{2} )^{2} =9x^{2} -6x^{3} +x^{4} \\\\b)~~(-y-3)^{2}=[(-1)\cdot (y+3)]^{2} = (-1)^{2}\cdot (y+3)^{2} =1\cdot (y^{2} +2\cdot y\cdot 3 +3^{2}) = y^{2} +6y+9\\\\c)~~(-2x+4)^{2} =(4-2x)^{2} =4^{2} -2\cdot 4\cdot 2x +(2x)^{2} =16-16x+4x^{2} \\\\d)~~(-y^{2} +x)^{2} =(x-y^{2} )^{2}=x^{2} -2\cdot x\cdot y^{2} +(y^{2} )^{2} =x^{2} -2xy^{2} +y^{4} \\\\[/tex]
[tex]e)~~(-x-y)^{2}=[(-1)\cdot (x+y)]^{2} = (-1)^{2}\cdot (x+y)^{2} =1\cdot (x^{2} +2\cdot x\cdot y +y^{2}) = x^{2} +2xy+y^{2}[/tex]
korzystam ze wzorów :
[tex](x+y)^{2} =x^{2} +2xy+y^{2} \\\\(x-y)^{2} =x^{2} -2xy+y^{2} \\\\(x\cdot y )^{n} =x^{n} \cdot y^{n}[/tex]
