If nC8 = nC2, find nC2.

Asked by Pragya Singh | 1 year ago |  101

##### Solution :-

We know that, if

$$^nC_a=\;^nC_b=a=b\;or\;m=a+b$$

$$^nC_8= \;^nC_2=n=8+2=10$$

$$^nC_2=^{10}C_2=\dfrac{10!}{(10-2)!2!}$$

$$\dfrac{10!}{2!8!}$$

$$\dfrac{10\times 9\times 8!}{2\times 1\times 8!}$$= 45

Answered by Abhisek | 1 year ago

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