Saved Bookmarks
| 1. |
If $ ^{n} \mathrm{C}_{8}=^{n} \mathrm{C}_{2}, $ find $ ^{n} \mathrm{C}_{2} $ |
|
Answer» If ⁿCₓ = ⁿCᵤ then, x + u = n Here, ⁿC₈ = ⁿC₂ so, according to results , n = 8 + 2 = 10 hence, n = 10 Hence 10C2=10!/8!2!=10*9/2=9*5=45 |
|