You are not logged in.
Pages: 1
1. Suppose that $x_{1}$ and $x_{2}$ different equation $ax^3+bx^2+cx+d=0$
Prove that: $x_{1}x_{2} \geq \frac{4ac-b^2} {4a^2}$
2. For the polynomial $f(x)=ax^2+bx+c$ knows that $f(x) \geq 0$ for all real numbers $x$ and $b>a$. Find min of expression: $P=\frac{a+b+c}{b-a}$
1.
(1) $\Leftrightarrow (x+2)^3=-6x^3\Leftrightarrow x+2=x\sqrt[3]{-6}\Leftrightarrow x=\frac{2}{\sqrt[3]{-6}-1}$
I have not solved the 2nd equation.
You could help me.
a. $7x^3+6x^2+12x+8=0$
b. $x^3-3x^2+3(\sqrt{2}+1)x-3-2\sqrt{2}=0$
Pages: 1