1) If A= [13121−1301] , then rank(A) is equal to A) 4 B) 1 C) 2 D) 3 Answer: Option DExplanation:A=[13121−1301]=[1310−5−30−9−2] [Applying R2→ R2 -2R1 , R3 → R3 -3R1 ] ≈[1310−5−300175] [R3→R3−95R2] ∴ rank (A)=3