Square of a + square of B + 1 / 2 * a * (B-A) - square of 1 / 2B - 1 / 2 * a * (a + b)

Square of a + square of B + 1 / 2 * a * (B-A) - square of 1 / 2B - 1 / 2 * a * (a + b)

Square of a + square of B + 1 / 2 * a * (B-A) - square of 1 / 2B - 1 / 2 * a * (a + b)
=Square of a + square of B + 1 / 2ab-1 / 2A square - 1 / 2B square - 1 / 2A square - 1 / 2Ab
=(A's Square-1 / 2A's Square-1 / 2A's Square) + (B's Square-1 / 2B's Square) + (1 / 2ab-1 / 2Ab)
=Square of 1 / 2B