mCn: if n >= 3, then find value of (n-3)C(r) + ...

[karan]

If n> 3 is a positive integer, then what will be the value of expression [sup:2dnkcpeb]n-3[/sup:2dnkcpeb]C[sub:2dnkcpeb]r[/sub:2dnkcpeb] + [sup:2dnkcpeb]n-3[/sup:2dnkcpeb]C[sub:2dnkcpeb]r-1[/sub:2dnkcpeb] + 3*([sup:2dnkcpeb]n-3[/sup:2dnkcpeb]C[sub:2dnkcpeb]r-2[/sub:2dnkcpeb]) + [sup:2dnkcpeb]n-3[/sup:2dnkcpeb]C[sub:2dnkcpeb]r-3[/sub:2dnkcpeb]

 

[stapel]

If n> 3 is a positive integer, then what will be the value of expression [sub:39vejbw4]n-3[/sub:39vejbw4]C[sub:39vejbw4]r[/sub:39vejbw4] + [sub:39vejbw4]n-3[/sub:39vejbw4]C[sub:39vejbw4]r-1[/sub:39vejbw4] + 3*([sub:39vejbw4]n-3[/sub:39vejbw4]C[sub:39vejbw4]r-2[/sub:39vejbw4]) + [sub:39vejbw4]n-3[/sub:39vejbw4]C[sub:39vejbw4]r-3[/sub:39vejbw4]

Are you given any information regarding the value of r, or the relationship between r and n?

What have you tried? How far have you gotten? Where are you stuck?

Please be complete. Thank you!

Eliz.