Test Index

JAMB Mathematics 2021 Paper

© africaexams.com

Question : 34

Total: 40

If the binary operation

*

is defined by m

*

n = mn + m + n for any real number m and n, find the identity of the elements under this operation

e = 1
e = -1
e = -2
e = 0

Solution:

Identity(e) : a $*$ e = a

m $*$ e = m...(i)

m $*$ e = me + m + e

Because m $*$ e = m

: m = me + m + e

m - m = e(m + 1)

e = $\frac{0}{m+1}$

e = 0

© africaexams.com

Go to Question:

Prev Question

Next Question