a b means return true if the value of a is equal to the value of b, otherwise return false.
a = b means assign the value of b to the variable a.
a - b = c -(a - b) = -c b - a = -c
a= (+a) or a= (-) b= 2a b= 2a c= (-a) c= (+a)
2a. (a, b and c are all equal.)
A.
by transitive property
A=B , A-B=B-B , A-B =0 B=C , B-B=C-B, 0=C-B So A-B=0 but also C-B=0 A-B=C-B ...add +b ...A-B+B=C-B+B , A=C
Yes.
If a is to b as c is to d, a x d = b x c. The product of the means (b & c) equals the product of the extremes (a & d).
Yes, a&b|c&d means (a&b)|(c&d), just like a&&bc&&d means (a&&b)(c&&d)
suppose x is in B. there are two cases you have to consider. 1. x is in A. 2. x is not in A Case 1: x is in A. x is also in B. then x is in A intersection B. Since A intersection B = A intersection C, then this means x is in A intersection C. this implies that x is in C. Case 2: x is not in A. then x is in B. We know that x is in A union B. Since A union B = A union C, this means that x is in A or x is in C. since x is not in A, it follows that x is in C. We have shown that B is a subset of C. To show that C is subset of B, we do the same as above.
a = 20 b = 60 c = 100
A=0 b=0 c=0