$^n{C_r}{ + ^{n - 1}}{C_r} + ......{ + ^r}{C_r}$ =
$^n{C_r}{ + ^{n - 1}}{C_r} + ......{ + ^r}{C_r}$ =
- A
$^{n + 1}{C_r}$
- B
$^{n + 1}{C_{r + 1}}$
- C
$^{n + 2}{C_r}$
- D
${2^n}$
Similar Questions
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- [IIT 2017]
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