Wzory:
[tex](x+y)^2=x^2+y^2+2xy\\\\(x-y)^2=x^2+y^2-2xy\\\\(x-y)(x+y)=x^2-y^2[/tex]
a] [tex](x+4)^2=x^2+4^2+2\cdot x\cdot4=x^2+16+8x[/tex]
b] [tex](x-2)^2=x^2+2^2-2\cdot x\cdot2=x^2+4-4x[/tex]
c] [tex](3x+2)^2=(3x)^2+2^2+2\cdot3x\cdot2=9x^2+4+12x[/tex]
