In binomial theorem, "sum of all coefficients" refers to the sum of all coefficients. X= 1 can be substituted into the calculation result, which is the result.

The sum of binomial coefficients can be determined by assignment method.

The binomial coefficient and formula are c (n, 0)+c (n, 1)+...+c (n, n) = 2 n.

Binomial coefficient, or combination number, is defined as the coefficient after X expansion in the form of (1+x)*6*7 (where n is a natural number and k is an integer). It can be seen from the definition that the value of binomial coefficient is an integer.

The significance of this theorem:

Newton invented calculus according to binomial theorem. ? [4] Its application in elementary mathematics mainly lies in some rough analysis, estimation and proof of identities.

This theorem also has its place in genetics, and its specific applications include: inferring the genotype and probability of self-bred offspring, inferring the phenotype and probability of self-bred offspring, inferring the phenotype distribution and probability of hybrid offspring, inferring the sex distribution and probability of husband and wife having children, inferring the gene or genotype frequency of balanced population, etc.