yes. It has to be either 0 or 1
ab = c ----- 1 bc = a ----- 2 ca = b ----- 3
Sub 1 in 2 b(ab) = a b^2 = 1 { assuming a is not equal to 0 } b=+1,-1
Sub 2 in 3 c(bc) = b c = +1,-1 { assuming a is not equal to 0 } and also a = +1,-1.
ie a,b,c = +1,-1 & 0.
Use the numbers 2, 3, 4 and 5 and the symbols + and = to make a true equation. Conditions: Each must be used exactly once and no other numbers or symbols can be used.
Is it possible to write down 1,2,3..100 in some order (one after an other), such that the sum of any two adjacent numbers is a prime number?
In a sequence of eleven real numbers, only two are shown. The product of every 3 successive boxes is 120. Find the sum of all the numbers in the boxes (including the two already open).
_ _ (6) _ _ _ _ _ _ (-4) _