numberoftermsintheexpansionof(x1+x2+.......+xr)nisn+r−1Cr−1∴numberofdistinctterms=n+4−1C4−1=n+3C3=((n+3)!n!×3!)=((n+3)(n+2)(n+1)6)
Find the number of dissimilar terms in the expansion of (x+y)32