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Numerical Ability
Permutation and Combination
what is k=0 to k=28 summation 3^k 28cK
a) 2^56
b)3*2^27
c) 3^29
d) 3*4^27
Read Solution (Total 2)
-
- a) 2^56
(1+x)^n = nc0 + nc1*x + nc2*x^2 + nc3*x^3 + ...+ ncn*x^n
put x=3 & n=28
(1+3)^28 = 3^0*28c0 + 3^1*28c1 + 3^2*28c2 + ...+3^28*28c28
=> 4^28 = k=0 to k=28 summation 3^k 28cK
=> 2^56 - 9 years agoHelpfull: Yes(36) No(0)
- ANSWER==> 2^56
as (1+3)^28= 3^0*28c0 + 3^1*28c1 +...+3^28*28c28 - 9 years agoHelpfull: Yes(3) No(0)
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