1) ∫dxx2+4x+13= A) 13tan−1(x+23)+C B) 16tan−1(x−1x+5)+C C) 3tan−1(x+23)+C D) 16tan−1(x+23)+C Answer: Option AExplanation: We have, l= ∫dxx2+4x+13 l=∫dxx2+4x+4+9=∫dx(x+2)2+(3)2 l= 13tan−1(x+23)+C