The term independent of x in x3+3x210 is

The general term is,  Tr+1=Cr   10x310-r2·3r2x2r =Cr   101310-r2×3r/2×x10-r2-2r  Therefore, for independent term of x , we  have, 10-r2-2r=0⇒r=2  Therefore, term independent of x =C(10,2)134×3=45×1×381=4527=53