Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(6x^2+0=0\)
- \(-2x^2+128=0\)
- \(-4x^2-15=-10x^2-9\)
- \(-5(5x^2-8)=-(29x^2-44)\)
- \(2x^2-32=0\)
- \(12x^2-248=7x^2-3\)
- \(-3(10x^2-8)=-(32x^2-416)\)
- \(-5(-6x^2-7)=-(-23x^2+973)\)
- \(11x^2+602=5x^2+2\)
- \(-4(-3x^2+9)=-(-17x^2+161)\)
- \(2x^2-242=0\)
- \(-3(-7x^2-9)=-(-18x^2-39)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(6x^2+0=0 \\
\Leftrightarrow 6x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{6}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-2x^2+128=0 \\
\Leftrightarrow -2x^2 = -128 \\
\Leftrightarrow x^2 = \frac{-128}{-2}=64 \\
\Leftrightarrow x = 8 \vee x = -8 \\
V = \Big\{-8, 8 \Big\} \\ -----------------\)
- \(-4x^2-15=-10x^2-9 \\ \Leftrightarrow -4x^2+10x^2=-9+15 \\
\Leftrightarrow 6x^2 = 6 \\
\Leftrightarrow x^2 = \frac{6}{6}=1 \\
\Leftrightarrow x = 1 \vee x = -1 \\
V = \Big\{-1, 1 \Big\} \\ -----------------\)
- \(-5(5x^2-8)=-(29x^2-44) \\ \Leftrightarrow -25x^2+40=-29x^2+44 \\
\Leftrightarrow -25x^2+29x^2=44-40 \\
\Leftrightarrow 4x^2 = 4 \\
\Leftrightarrow x^2 = \frac{4}{4}=1 \\
\Leftrightarrow x = 1 \vee x = -1 \\
V = \Big\{-1, 1 \Big\} \\ -----------------\)
- \(2x^2-32=0 \\
\Leftrightarrow 2x^2 = 32 \\
\Leftrightarrow x^2 = \frac{32}{2}=16 \\
\Leftrightarrow x = 4 \vee x = -4 \\
V = \Big\{-4, 4 \Big\} \\ -----------------\)
- \(12x^2-248=7x^2-3 \\ \Leftrightarrow 12x^2-7x^2=-3+248 \\
\Leftrightarrow 5x^2 = 245 \\
\Leftrightarrow x^2 = \frac{245}{5}=49 \\
\Leftrightarrow x = 7 \vee x = -7 \\
V = \Big\{-7, 7 \Big\} \\ -----------------\)
- \(-3(10x^2-8)=-(32x^2-416) \\ \Leftrightarrow -30x^2+24=-32x^2+416 \\
\Leftrightarrow -30x^2+32x^2=416-24 \\
\Leftrightarrow 2x^2 = 392 \\
\Leftrightarrow x^2 = \frac{392}{2}=196 \\
\Leftrightarrow x = 14 \vee x = -14 \\
V = \Big\{-14, 14 \Big\} \\ -----------------\)
- \(-5(-6x^2-7)=-(-23x^2+973) \\ \Leftrightarrow 30x^2+35=23x^2-973 \\
\Leftrightarrow 30x^2-23x^2=-973-35 \\
\Leftrightarrow 7x^2 = -1008 \\
\Leftrightarrow x^2 = \frac{-1008}{7} < 0 \\
V = \varnothing \\ -----------------\)
- \(11x^2+602=5x^2+2 \\ \Leftrightarrow 11x^2-5x^2=2-602 \\
\Leftrightarrow 6x^2 = -600 \\
\Leftrightarrow x^2 = \frac{-600}{6} < 0 \\
V = \varnothing \\ -----------------\)
- \(-4(-3x^2+9)=-(-17x^2+161) \\ \Leftrightarrow 12x^2-36=17x^2-161 \\
\Leftrightarrow 12x^2-17x^2=-161+36 \\
\Leftrightarrow -5x^2 = -125 \\
\Leftrightarrow x^2 = \frac{-125}{-5}=25 \\
\Leftrightarrow x = 5 \vee x = -5 \\
V = \Big\{-5, 5 \Big\} \\ -----------------\)
- \(2x^2-242=0 \\
\Leftrightarrow 2x^2 = 242 \\
\Leftrightarrow x^2 = \frac{242}{2}=121 \\
\Leftrightarrow x = 11 \vee x = -11 \\
V = \Big\{-11, 11 \Big\} \\ -----------------\)
- \(-3(-7x^2-9)=-(-18x^2-39) \\ \Leftrightarrow 21x^2+27=18x^2+39 \\
\Leftrightarrow 21x^2-18x^2=39-27 \\
\Leftrightarrow 3x^2 = 12 \\
\Leftrightarrow x^2 = \frac{12}{3}=4 \\
\Leftrightarrow x = 2 \vee x = -2 \\
V = \Big\{-2, 2 \Big\} \\ -----------------\)