Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(12x^2+1375=5x^2+3\)
- \(8x^2+968=0\)
- \(3(2x^2+8)=-(-11x^2-344)\)
- \(5(-4x^2+3)=-(17x^2+660)\)
- \(-3(6x^2-8)=-(19x^2-24)\)
- \(-2(-7x^2-9)=-(-6x^2+54)\)
- \(-2(-2x^2+6)=-(0x^2-564)\)
- \(3(7x^2-4)=-(-16x^2+732)\)
- \(14x^2-850=9x^2-5\)
- \(4(-6x^2+6)=-(29x^2-24)\)
- \(x^2-144=0\)
- \(-11x^2-793=-3x^2+7\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(12x^2+1375=5x^2+3 \\ \Leftrightarrow 12x^2-5x^2=3-1375 \\
\Leftrightarrow 7x^2 = -1372 \\
\Leftrightarrow x^2 = \frac{-1372}{7} < 0 \\
V = \varnothing \\ -----------------\)
- \(8x^2+968=0 \\
\Leftrightarrow 8x^2 = -968 \\
\Leftrightarrow x^2 = \frac{-968}{8} < 0 \\
V = \varnothing \\ -----------------\)
- \(3(2x^2+8)=-(-11x^2-344) \\ \Leftrightarrow 6x^2+24=11x^2+344 \\
\Leftrightarrow 6x^2-11x^2=344-24 \\
\Leftrightarrow -5x^2 = 320 \\
\Leftrightarrow x^2 = \frac{320}{-5} < 0 \\
V = \varnothing \\ -----------------\)
- \(5(-4x^2+3)=-(17x^2+660) \\ \Leftrightarrow -20x^2+15=-17x^2-660 \\
\Leftrightarrow -20x^2+17x^2=-660-15 \\
\Leftrightarrow -3x^2 = -675 \\
\Leftrightarrow x^2 = \frac{-675}{-3}=225 \\
\Leftrightarrow x = 15 \vee x = -15 \\
V = \Big\{-15, 15 \Big\} \\ -----------------\)
- \(-3(6x^2-8)=-(19x^2-24) \\ \Leftrightarrow -18x^2+24=-19x^2+24 \\
\Leftrightarrow -18x^2+19x^2=24-24 \\
\Leftrightarrow x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{1}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-2(-7x^2-9)=-(-6x^2+54) \\ \Leftrightarrow 14x^2+18=6x^2-54 \\
\Leftrightarrow 14x^2-6x^2=-54-18 \\
\Leftrightarrow 8x^2 = -72 \\
\Leftrightarrow x^2 = \frac{-72}{8} < 0 \\
V = \varnothing \\ -----------------\)
- \(-2(-2x^2+6)=-(0x^2-564) \\ \Leftrightarrow 4x^2-12=0x^2+564 \\
\Leftrightarrow 4x^2+0x^2=564+12 \\
\Leftrightarrow 4x^2 = 576 \\
\Leftrightarrow x^2 = \frac{576}{4}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)
- \(3(7x^2-4)=-(-16x^2+732) \\ \Leftrightarrow 21x^2-12=16x^2-732 \\
\Leftrightarrow 21x^2-16x^2=-732+12 \\
\Leftrightarrow 5x^2 = -720 \\
\Leftrightarrow x^2 = \frac{-720}{5} < 0 \\
V = \varnothing \\ -----------------\)
- \(14x^2-850=9x^2-5 \\ \Leftrightarrow 14x^2-9x^2=-5+850 \\
\Leftrightarrow 5x^2 = 845 \\
\Leftrightarrow x^2 = \frac{845}{5}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(4(-6x^2+6)=-(29x^2-24) \\ \Leftrightarrow -24x^2+24=-29x^2+24 \\
\Leftrightarrow -24x^2+29x^2=24-24 \\
\Leftrightarrow 5x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{5}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(x^2-144=0 \\
\Leftrightarrow x^2 = 144 \\
\Leftrightarrow x^2 = \frac{144}{1}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)
- \(-11x^2-793=-3x^2+7 \\ \Leftrightarrow -11x^2+3x^2=7+793 \\
\Leftrightarrow -8x^2 = 800 \\
\Leftrightarrow x^2 = \frac{800}{-8} < 0 \\
V = \varnothing \\ -----------------\)