Question

I don't understand the highlighted part of solution
http://i.imgur.com/0quFs.png

Answer 1

hint: use of distributive property
(x+y)*(w+z)= x*w + x*z + y*w + y*z
does this help ?

Answer 2

This is what I got after using distribution:
(A∩A^c)U(A∩B^c)U(B∩A^c)U(B∩B^c)
As you can see I got (A∩A^c)
In solution it is (AUA^c)

Answer 3

@tux u are absolutely correct
there is printing mistake in that step,
then again next step there is correct

Answer 4

because A∩A^c is null as shown there.

Answer 5

A U A^c = U
A∩A^c={}
You are right. Thanks

Answer 6

^^ thats right too.
welcome :)