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Va rog mult ajutati-ma la acest exercitiu:
Utilizind relatiile lui Viete,rezolvati in R ecuatia:
a)x^2-5x+6=0,
b)x^2+5x-14=0.


Răspuns :

a)
   [tex] \left \{ {{x1+x2=5} \atop {x1*x2=6}} \right. [/tex] ⇔[tex] \left \{ {{x1=2} \atop {x2=3}} \right. [/tex]
b)
[tex] \left \{ {{x1+x2=-5} \atop {x1+x2=-14}} \right. [/tex]⇔[tex] \left \{ {{x1=-7} \atop {x2=2}} \right. [/tex]
a)x^2-5x+6=0
Δ=b²-4ac
Δ=25-24
Δ=1
x₁=(-b-√Δ)/2a=(5-1)/2=4/2=2
x₂=(-b+√Δ)/2a=6/2=3
b)x^2+5x-14=0
Δ=25+56
Δ=81
x₁=(-5-9)/2=(-14)/2=-7
x₂=4/2=2