Calculate the following reel integrals by using a given contour in the complex domain. (Hint: The contour is the semi circle with radius R, when R o. Think that the result of contour equals result of residue theorem. For sin(x) and cos(x), use euler's formula) dx a-f 1000 x +9 b-500 c- 50 cos C- dx x4+16 cos(x)dx x+9 d-10000 - co sin(x) dx x+9 1 Y CR