1)
(x+3)²=
x²+2x•3+3²=
x²+6x+9
2)
x=[tex] \sqrt{2} [/tex]
y=1
(x-y)(x+y)=
[tex]( \sqrt{2} - 1)( \sqrt{2} + 1) = \\ \\ \sqrt{2} ^{2} - {1}^{2} = \\ \\ 2 - 1 = \\ \\ 1 [/tex]
3)
2ax-4bx-6x=
[tex]2x( \frac{2ax}{2x} + \frac{ - 4bx}{2x} + \frac{ - 6x}{2x}) = [/tex]
2x(a-2b+3)
