WAEC - Further Mathematics (2012 - No. 15)
A binary operation, \(\Delta\), is defined on the set of real numbers by \(a \Delta b = a + b + 4\). Find the identity element.
4
2
\(\frac{1}{4}\)
-4
คำอธิบาย
\(a \Delta b = a + b + 4\)
\(a \Delta e = a + e + 4 = a\)
\(e = a - a - 4 = -4\)