If n and r are two positive integers such that n ≥ r, then ^ n C_ r-1 + ^ n C_ r is equal…
Mathematics · JEE Main · NTA Exams — Permutations and Combinations
If n and r are two positive integers such that n ≥ r, then \({ }^{n} C_{r-1}+{ }^{n} C_{r}\) is equal to :
- \({ }^{n} c_{n-n}\)
- \({ }^{n} c_{p}\)
- \({ }^{n-1} C_{r}\)
- \({ }^{n+1} \mathrm{C}_{n}\)
Answer
(D) ^ n+1 C _ n
Sign up free on Edukali to view the step-by-step worked solution and practice thousands of similar questions.
Related practice questions
- The number of 3 digit odd numbers, that can be formed by using the digits 1, 2, 3, 4, 5, 6 when the…
- There are 9 candidates for an examination out of which 3 are appearing in Mathematics and remaining 6 are…
- The letters of word “Radhika” are permuted and arranged in alphabetical order as in English dictionary. The…
- In how many ways can two balls of the same colour be selected out of 4 distinct black and 3 distinct white…
- Total numbers of 6-digit numbers in which only and all the five digits 1, 3, 5, 7 and 9 appear, is
- Number of rectangles in figure shown which are not squares is : array |l|l|l|l|l|l| & & & & & & & & & & & & &…
- There are p points in a plane, no three of which are in the same straight line with the exception of q points…
- If all permutations of the letters of the word AGAIN are arranged as in dictionary, then fiftieth word is
More Permutations and Combinations questions · Browse all practice questions