RRB NTPC · Question 35
\({\left( {4x - 7} \right)^2} = \;?\) A. 4x^2 – 56x + 49 B. 4x^2 – 14x + 49 C. 16x^2 + 14x + 49 D. 16x^2 – 56x + 49
Show answer & explanation
Answer: (D) D
Explanation
(a − b)² = a² − 2ab + b². With a = 4x and b = 7: 16x² − 56x + 49.