Question

na którym etapie poniższego rachunku popełniono błąd?

x=3 y=1 z=2

x=y+z

x(x-y)=(y+z)(x-y)

x^2-xy=yx +zx-y^2-zy

x^2-xy-zx=xy-y^2-zy

x(x-y-z)=y(x-y-z)

x=y

czyli:

3=1

Answer 1

x=3 y=1 z=2

x=y+z

x(x-y)=(y+z)(x-y)

 3(3-1)=(1+2)(3-1)

6=6

 

x^2-xy=yx +zx-y^2-zy

9-3=3+6-1-2

6=6

x^2-xy-zx=xy-y^2-zy

 

9-3-6=3-1-2

0=0

x(x-y-z)=y(x-y-z)

3(3-1-2)=1(3-1-2)

0=0

x=y

czyli:

3=1