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Descompuneti 2x patrat -7x+3

Răspuns :

[tex]2x^2-7x+3=0\Rightarrow \Delta=b^2-4ac=49-24=25\Rightarrow [/tex]

[tex]x_{1;2}=\dfrac{7\pm5}{4};\ x_1=3;\ x_2=\dfrac12[/tex]

[tex]2x^2-7x+3=2(x-3)(x-\dfrac12)=(x-3)(2x-1)[/tex]

Atașând ecuația de gradul 2, avem:

[tex]2 x^{2} -7x+3=0[/tex]
Δ=b²-4ac= 49-4*2*3=49-24=25
[tex] x_{1} = \frac{-b+ \sqrt{delta} }{2a} = \frac{7+ \sqrt{25} }{4}= \frac{12}{4} =3[/tex]
[tex] x_{2} = \frac{-b- \sqrt{delta} }{2a}=\frac{7- \sqrt{25} }{4}= \frac{2}{4} = \frac{1}{2} [/tex]

Astfel, avem descompunerea [tex]a(x-x_{1})(x-x_{2})=2(x-3)(x- \frac{1}{2} )= (x-3)(2x-1)[/tex]