Question

Rezolvati in N ecuatia.

Answer 1

Prelucrezi ecuatia

8*(n+1)!/5!*(n+1-5)!=3*n*(n-1)*(n-2)

8*(n+1)!/5!*(n-4)!=3n*(n-1)*(n-2)

8*(n-4)!*(n-3)*(n-2)(n-1)*n/5!*(n-4)!=3n*(n-1)*(n-2)

8(n-3)(n-2)*(n-1)*n/5!=3n(n-1)(n-2)

Imparti    egalitatea     prin (n-2)*(n-1)*n

8(n-3)/5!=3

8(n-3)=3*5!

8(n-3)=3*120 Imparti    egalitatea     pri   8

n-3=3*15

n-3=45

n=3+45

n=48