Simplify 
and find its value for
(i) 
(ii) 
(iii) 
(i) Substituting a = 0 in the expression 
(ii) Substituting a = 1 in the expression 
(iii) Substituting a = -1 in the expression 
7
Simplify and find its value for
(i)
(ii)
(iii)
(i) Substituting a = 0 in the expression
(ii) Substituting a = 1 in the expression
(iii) Substituting a = -1 in the expression