Question

ajutor va rog mult ajutatima​

Answer 1

Răspuns: $\color{red}\Large \boxed{\bf \bigg\{-3;~ \dfrac{1}{2};~1 \bigg\}}$

Explicație pas cu pas:

$\large \bf 2x^{2} +5x-3 = 0$

$\large \bf 2x^{2} +6x-x-3 = 0$

$\large \bf 2x(x+3)-(x+3) = 0$

$\large \bf (x+3)\cdot(2x-1) = 0$

$\large \bf \implies (x+3)=0\implies \boxed{\bf x_{1} = -3}$

$\large \bf \implies (2x-1)=0\implies \boxed{\bf x_{2} = \dfrac{1}{2}=0,5}$

$\large \bf \implies \boxed{\bf x\in \bigg\{-3; ~\dfrac{1}{2}\bigg\}}$

$\large \bf \boxed{\bf A= \bigg\{-3; ~\dfrac{1}{2}\bigg\}}$

$\large \bf A~ \cup ~\big\{-3; 1 \big\} \implies \bigg\{-3; ~\dfrac{1}{2}\bigg\} \cup \big\{-3; 1 \big\} = \boxed{\bf \bigg\{-3; \dfrac{1}{2}; 1 \bigg\}}$

#copaceibrainly

Answer 2

Răspuns:

{ - 3 ; 1/2 ; 1 }

Explicație pas cu pas:

2x² + 5x - 3 = 0

$x_{1,2}=\frac{-5+/-\sqrt{5^{2}-4*2*(-3)} }{2*2}\\\\ x_{1,2}=\frac{-5+/-\sqrt{49} }{4}\\\\ x_{1,2}=\frac{-5+/-7}{4}\\\\x_{1}=\frac{-5+7}{4}=\frac{2}{4}=\frac{1}{2}\\\\x_{2}=\frac{-5-7}{4}=\frac{-12}{4}=-3$

A = { - 3 ; 1/2 }

A U { - 3 ; 1 } = { - 3 ; 1/2 ; 1 }