UGC NET Questions (Paper – 1)

Statements A, B and C are standard algebraic identities for binomial squares and difference of squares, while D correctly results from subtracting the two square expansions and simplifies many expressions quickly. Statement E is false because these identities are widely used in aptitude problems to perform rapid simplification or mental calculation. Therefore, the set consisting of A, B, C and D only is correct.

Option A:
Option A is correct as it lists all and only the valid identities, illustrating how they combine to yield useful simplifications such as 4ab, and it rightly omits E, which denies their important role in exam problems.

Option B:
Option B is incomplete since it omits D and thus misses the composite application of the identities, which is frequently tested when candidates are asked to simplify expressions like (a + b)² − (a − b)².

Option C:
Option C is also incomplete as it excludes A, failing to state the most commonly used identity for (a + b)² explicitly, even though the other identities are present. Without A, the picture is not complete.

Option D:
Option D is incorrect because it leaves out B and therefore fails to state the identity for (a − b)², which is as important as the identity for (a + b)² in exam contexts.