Replace x with π/2 - x to get the equivalent integral

but the integrand is even, so this is really just

Substitute x = 1/2 arccot(u/2), which transforms the integral to

There are lots of ways to compute this. What I did was to consider the complex contour integral

where γ is a semicircle in the complex plane with its diameter joining (-R, 0) and (R, 0) on the real axis. A bound for the integral over the arc of the circle is estimated to be

which vanishes as R goes to ∞. Then by the residue theorem, we have in the limit

and it follows that

Answer:
3-2x=15
Step-by-step explanation:
add 3 to both sides makes -2x=18. divide -2 from both side gets the answer x=-9, so the answer is C, -9
There would be 3 2/12 left.
2/3 x 1/4 = 2/12
Hope this helps!
Sorryyyy :C
Answer:
x = -8
Step-by-step explanation:
9+8x-4-5x=-19
5+8x-5x=-19
5+3x=-19
-5 =-19
3x = -24
3/3 = -24/3
x= -8