find n if 2nC3=24 .nC4       find nC2?

Dear Student,
Please find below the solution to the asked query:
2nC3=24×nC42n!3!×2n-3!=24×n!4!×n-4!2n2n-12n-21×2×3=24×n×n-1n-2n-31×2×3×416×2n2n-12n-2=n×n-1n-2n-316×2n×2n-1×2n-1=n×n-1n-2n-313×22n-1=n-2n-322n-1=3n-2n-34n-2=3n2-5n+64n-2=3n2-15n+183n2-19n+20=03n2-15n-4n+20=03nn-5-4n-5=0n-53n-4=0n-5=0  or  3n-4=0n=5, 43But n can not be fraction.n=5
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