Coefficient of the term independent of x in the expansion x+1x4x−1x12is

x+1x4x−1x12=x+1x4x−1x4x−1x8=x2−1x24x−1x8= 4C0x8−4C1x4+4C2−4C31x4+4C41x8× 8C0x8−8C1x6+8C2x4−⋯+8C81x8 ∴ Coefficient of the term independent of x = 4C0 8C8− 4C1 8C6+ 4C2 8C4− 4C3 8C2+ 4C4 8C0=198