The expression \((12.86 \times 12.86 + 12.86 \times p + 0.14 \times 0.14)\) will be a perfect square for \(p\) equal to:
Answer: A
\((a + b)^2 = a^2 + 2ab + b^2\)
\(12.86 \times 12.86 + 12.86 \times p + 0.14 \times 0.14\)
\(= (12.86)^2 + 12.86 \times p + (0.14)^2\)
This can be written as,
\((12.86 + 0.14)^2 = 13^2\)
If, \(12.86 \times p = 2 \times 12.86 \times 0.14\)
i.e., if \(p = 2 \times 0.14 = 0.28\)