Expand the following, using suitable identities: (14a−12b+1)2 [3 MARKS]
Formula: 1 Mark
Substitution: 1 Mark
Calculation: 1 Mark
(14a−12b+1)2
Using the identity
(a+b+c)2=a2+b2+c2+2(ab+bc+ca) ....(1)
a=14a,b=−12b,c=1
Substituting the values of a,b,c in identity(1)
=(14a)2+(−12b)2+(1)2+2(14a)(−12b)+2(−12b)(1)+2(1)(14a)
=116a2+14b2+1−14ab−b+12a