1)

Value of π3π611+cotxdx is


A) π6

B) π12

C) 12π

D) None of these

Answer:

Option B

Explanation:

I = π3π611+cotxdx

π3π6sinxsinx+cosxdx ...(i)

Then I=

π3π6sin(π2x)sin(π2x)+cos(π2x)dx 

I = π3π6cosx)cosx)+sinx)dx ...(ii)

Adding (i) and (ii) we get

2I = π3π6sinx+cosx)cosx)+sinx)dx

2I=π3π61.dx=[x]π3π6

= π3π6=π6 

I = π12