The value _ r =0 ^ 22 ^ 22 C _ r ^ 23 C _ r is ....... - Vidyadip

MCQ

The value $\sum \limits_{ r =0}^{22}{ }^{22} C _{ r }{ }^{23} C _{ r }$ is $.......$

✓
${ }^{45} C _{23}$
B
${ }^{44} C _{23}$
C
${ }^{45} C _{24}$
D
${ }^{44} C _{22}$

✓

Answer

Correct option: A.

${ }^{45} C _{23}$

a
$\sum \limits_{ r =0}^{22}{ }^{22} C _{ r } \cdot{ }^{23} C _{ r }=\sum \limits_{ r =0}^{22}{ }^{22} C _{ r } \cdot{ }^{23} C _{23- r }$

$={ }^{45} C _{23}$

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