Identify binomial form: We need to find the square of the binomial (2z−1). This is in the form of (a−b)2, which is a special case of binomial expansion.Special case: (a−b)2=a2−2ab+b2
Determine a and b: Identify the values of a and b in the binomial (2z−1)2. Compare (2z−1)2 with (a−b)2. a=2zb=1
Apply binomial formula: Apply the square of a binomial formula to expand (2z−1)2.(a−b)2=a2−2ab+b2(2z−1)2=(2z)2−2(2z)(1)+(1)2