Question

sa se determine xmai mare decat
0 stiind ca numerele x,4 si x-6 sunt in progresie geometrica

Answer 1

3 numere a, b, c se afla in progresie geometrica, atunci b²=a*c
deci 4²=x(x-6)
=> x²-6x-16=0
Se rezolva ecuatia de gradul 2:
Δ=36-4*1*(-16)=36+64=100
x1=(6-√100)/2=6-10)/2=-4/2=-4 <0
x2=6+√100)/2=16/2=8 >0

Deci x=8 >0