Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(-x^2-98=-4x^2+10\)
- \(-6x^2-4=-10x^2-4\)
- \(-x^2+9=0\)
- \(-3(-9x^2+10)=-(-23x^2-226)\)
- \(4(5x^2+6)=-(-27x^2+984)\)
- \(4(2x^2+8)=-(-12x^2+452)\)
- \(6x^2-24=0\)
- \(-6x^2+0=0\)
- \(7x^2-175=0\)
- \(-x^2-1188=-8x^2-5\)
- \(6x^2+600=0\)
- \(7x^2+1183=0\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(-x^2-98=-4x^2+10 \\ \Leftrightarrow -x^2+4x^2=10+98 \\
\Leftrightarrow 3x^2 = 108 \\
\Leftrightarrow x^2 = \frac{108}{3}=36 \\
\Leftrightarrow x = 6 \vee x = -6 \\
V = \Big\{-6, 6 \Big\} \\ -----------------\)
- \(-6x^2-4=-10x^2-4 \\ \Leftrightarrow -6x^2+10x^2=-4+4 \\
\Leftrightarrow 4x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{4}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-x^2+9=0 \\
\Leftrightarrow -x^2 = -9 \\
\Leftrightarrow x^2 = \frac{-9}{-1}=9 \\
\Leftrightarrow x = 3 \vee x = -3 \\
V = \Big\{-3, 3 \Big\} \\ -----------------\)
- \(-3(-9x^2+10)=-(-23x^2-226) \\ \Leftrightarrow 27x^2-30=23x^2+226 \\
\Leftrightarrow 27x^2-23x^2=226+30 \\
\Leftrightarrow 4x^2 = 256 \\
\Leftrightarrow x^2 = \frac{256}{4}=64 \\
\Leftrightarrow x = 8 \vee x = -8 \\
V = \Big\{-8, 8 \Big\} \\ -----------------\)
- \(4(5x^2+6)=-(-27x^2+984) \\ \Leftrightarrow 20x^2+24=27x^2-984 \\
\Leftrightarrow 20x^2-27x^2=-984-24 \\
\Leftrightarrow -7x^2 = -1008 \\
\Leftrightarrow x^2 = \frac{-1008}{-7}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)
- \(4(2x^2+8)=-(-12x^2+452) \\ \Leftrightarrow 8x^2+32=12x^2-452 \\
\Leftrightarrow 8x^2-12x^2=-452-32 \\
\Leftrightarrow -4x^2 = -484 \\
\Leftrightarrow x^2 = \frac{-484}{-4}=121 \\
\Leftrightarrow x = 11 \vee x = -11 \\
V = \Big\{-11, 11 \Big\} \\ -----------------\)
- \(6x^2-24=0 \\
\Leftrightarrow 6x^2 = 24 \\
\Leftrightarrow x^2 = \frac{24}{6}=4 \\
\Leftrightarrow x = 2 \vee x = -2 \\
V = \Big\{-2, 2 \Big\} \\ -----------------\)
- \(-6x^2+0=0 \\
\Leftrightarrow -6x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-6}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(7x^2-175=0 \\
\Leftrightarrow 7x^2 = 175 \\
\Leftrightarrow x^2 = \frac{175}{7}=25 \\
\Leftrightarrow x = 5 \vee x = -5 \\
V = \Big\{-5, 5 \Big\} \\ -----------------\)
- \(-x^2-1188=-8x^2-5 \\ \Leftrightarrow -x^2+8x^2=-5+1188 \\
\Leftrightarrow 7x^2 = 1183 \\
\Leftrightarrow x^2 = \frac{1183}{7}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(6x^2+600=0 \\
\Leftrightarrow 6x^2 = -600 \\
\Leftrightarrow x^2 = \frac{-600}{6} < 0 \\
V = \varnothing \\ -----------------\)
- \(7x^2+1183=0 \\
\Leftrightarrow 7x^2 = -1183 \\
\Leftrightarrow x^2 = \frac{-1183}{7} < 0 \\
V = \varnothing \\ -----------------\)