O $42. The length of the arc of y = In cos x from x = to x = equals (A) In V3 + 2 (B) 2 (C) In (1 + V3-V2) V2 + 1 (D) V3-2 In (v3 + 2) (E) In (V2 + 1) *43. The length of one arch of the cycloid *=/ - sint y = 1- cost equals - cost (A) VI - cost di (B) dt (C) V2 - 2 cost dt 2 1 - cost (D) V2 - 2cost di (E) 2 dt 2 $44. The length of the arc of the parabola 4x = y' cut off by the line x = 2 is given by the integral (A) Vx' + 1 dx (B) Vary dy ( @ ) VI + x dx (2 v2 (D) 4 + y' dy (E) none of these