What is the sum of all the coefficients in (1+x)7 binomial expansion?

1 Answer
Aug 5, 2017

2^7=128.

Explanation:

Knowing that, the Expansion of (1+x)^7, is a poly. of degree 7,

suppose that,

(1+x)^7=a_0+a_1x+a_2x^2+...+a_7x^7....(star).

Note : We can actually expand (1+x)^7, but we don't need that.

:. x=1,

rArr 2^7=a_0+a_1+a_2+...+a_7"=the desired sum of the co-effs."