The idea may be explained to the child orally. To enhance the understanding level of
the child the procedure followed in teaching the commutative property may be followed
with three groups of beads.
- Additive identity
For any two real numbers a and 0, if a + 0 = 0 + a = a, then we say that 0 is the
additive identity. That is with respect to addition, if 0 is added to any number then
the resultant is always the number and hence 0 is said to be the additive identity.
The idea may be explained to the child orally.
- Multiplicative identity
If the product on multiplying two numbers is equal to 1, then the two numbers are
said to be multiplicative inverses of each other, and 1 is the multiplicative identity.
For any real number ‘a’ its multiplicative inverse is denoted as^1 a. That is when ‘a’
and a^1 are multiplied together then the resultant is equal to 1.
Eg. : The product of 5 and 51 is equal to 1 and hence 51 is the multiplicative inverse
of 5 and vice versa.
The idea may be explained to the child orally assisted by necessary text material in
Braille.