Q9 of 51 Page 18

If a and b denote the sum of the coefficients in the expansions of and respectively, then write the relation between a and b.

Given:


(1-3x+10x2)n


Sum of coefficients = a


a


=(23)n


=(2n)3


(1+x2)n


Sum of coefficients = b


b= (1+1)n


=2n


Put value of b in a; we get:


a=b3


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