200 - a2 = (10*wurzel(2) - a) * (10*wurzel(2) + a)
177 - x2 = (wurzel(177)-x)* (wurzel(177)+x) x2 - 2xy + y2 + 5=(x-y)^2 + 5
ertfernen der Klammern
a) a ( b - a )2 = a*(b^2 -2ab+a^2)=ab^2-2a^2 b+a^3
b) ( y + x )2 x = (y^2+2yx +x^2 ) * x = xy^2 +2yx^2 + x^3
c) x ( x + y ) ( x - y ) = x^2 - y^2
d) ( 12 - x )2 x = (144 - 24x + x^2 )*x = 144x - 24x^2 + x^3
e) 7 ( 12 + x ) ( 12 - x ) = 7*(144-x^2) = 1008 - 7x^2