Please explain point no vi?

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Answer 1 · 2018-04-25T07:34:11

See the explanation below

#{((a_1+a_2)^1=a_1+a_2),(m=1),(n=2),(S="^(n-1)C_(m+n-1)=(2!)/(1!xx1!)=2):}#

#{((a_1+a_2)^2=a_1^2+a_2^2+2a_1a_2),(m=2),(n=2),(S="^(n-1)C_(m+n-1)=(3!)/(1!xx2!)=3):}#

#{((a_1+a_2+a_3)^2=a_1^2+a_2^2+a_3^2+2(a_1a_2+a_2a_3+a_1a_3)),(m=2),(n=3),(S="^(n-1)C_(m+n-1)=(4!)/(2!xx2!)=6):}#

The number of terms is

#= "^(m+n-1)C_(n-1)=((m+n-1),(n-1))#

#=((m+n-1)!)/((n-1)!(m+n-1-n+1)!)#

#=((m+n-1)!)/((n-1)!(m)!)#