Rozwiąż nierówność
: 8 maja 2009, o 18:49
\(\displaystyle{ -2x^3+4x^2+9x+3}\)
\(\displaystyle{ -2x^3+4x^2+9x+3:x+1=-2x^2+6x+3}\)
\(\displaystyle{ \Delta=b^2-4ac=6^2-4*(-2)*3=36+24=60}\)
\(\displaystyle{ x_1=\frac{-6-\sqrt{60}}{2*(-2)}=\frac{-6-\sqrt{4*15}}{-4}=\frac{-6-2\sqrt{15}}{-4}=\frac{3-2\sqrt{15}}{2}=3-\sqrt{15}}\)
Powinno: \(\displaystyle{ \frac{3-\sqrt{15}}{2}}\)
\(\displaystyle{ -2x^3+4x^2+9x+3:x+1=-2x^2+6x+3}\)
\(\displaystyle{ \Delta=b^2-4ac=6^2-4*(-2)*3=36+24=60}\)
\(\displaystyle{ x_1=\frac{-6-\sqrt{60}}{2*(-2)}=\frac{-6-\sqrt{4*15}}{-4}=\frac{-6-2\sqrt{15}}{-4}=\frac{3-2\sqrt{15}}{2}=3-\sqrt{15}}\)
Powinno: \(\displaystyle{ \frac{3-\sqrt{15}}{2}}\)