please tell me the formulas for solvilng the question related to binomial coefficient?

Ans:
Hello Student,
Please find answer to your question below

Here are the formulas for binomial coefficient:
1)ⁿC_r= [n!/(r!(n-r)!)]
2) ⁿC_r= ⁿC_s
Either r = s or r + s = n
3) ⁿC_r+ ⁿC_r+1= ⁿ⁺¹C_r+1
4)ⁿ⁺¹C_r+1= (n+1/r+1)ⁿC_r
5) ⁿC_r+1/ⁿC_r= n-r/r+1