If ^8 C_r = ^8 C_ r + 2 , then the value of ^r C_2 is - Vidyadip

Question

If $^8{C_r}{ = ^8}{C_{r + 2}}$, then the value of $^r{C_2}$ is

✓

Answer

b
(b) $^8{C_r}{ = ^8}{C_{r + 2}}$

$\Rightarrow 8 - r = r + 2 $

$\Rightarrow r = 3$

Hence$^3{C_2} = 3$.

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