Question

a+b=5
a^2+b^2=15
aflati A si B.

Answer 1

a+b=5
2ab= (a+b)²- (a²+b²)
2ab= 5²-15=25-15=10
ab=5

a+b=5
ab=5

Construim ecuatia
z²-Sz+P=0
z²-5z+5=0

z1,2= [5+-√(25-20)]/2
z1,2=(5+-√5)/2

a=(5+√5)/2
 b= (5-√5)/2


sau
a=(5-√5)/2
b= (5+√5)/2

care verifica ipoteza