Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(3x^2-108=0\)
- \(3(3x^2-6)=-(-14x^2+18)\)
- \(-11x^2+852=-6x^2+7\)
- \(10x^2-480=4x^2+6\)
- \(2x^2+450=0\)
- \(12x^2-94=8x^2+6\)
- \(-8x^2+1352=0\)
- \(3x^2-3=0\)
- \(-7x^2+0=0\)
- \(10x^2+263=6x^2+7\)
- \(4x^2-900=0\)
- \(-3(9x^2+6)=-(20x^2-45)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(3x^2-108=0 \\
\Leftrightarrow 3x^2 = 108 \\
\Leftrightarrow x^2 = \frac{108}{3}=36 \\
\Leftrightarrow x = 6 \vee x = -6 \\
V = \Big\{-6, 6 \Big\} \\ -----------------\)
- \(3(3x^2-6)=-(-14x^2+18) \\ \Leftrightarrow 9x^2-18=14x^2-18 \\
\Leftrightarrow 9x^2-14x^2=-18+18 \\
\Leftrightarrow -5x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-5}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-11x^2+852=-6x^2+7 \\ \Leftrightarrow -11x^2+6x^2=7-852 \\
\Leftrightarrow -5x^2 = -845 \\
\Leftrightarrow x^2 = \frac{-845}{-5}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(10x^2-480=4x^2+6 \\ \Leftrightarrow 10x^2-4x^2=6+480 \\
\Leftrightarrow 6x^2 = 486 \\
\Leftrightarrow x^2 = \frac{486}{6}=81 \\
\Leftrightarrow x = 9 \vee x = -9 \\
V = \Big\{-9, 9 \Big\} \\ -----------------\)
- \(2x^2+450=0 \\
\Leftrightarrow 2x^2 = -450 \\
\Leftrightarrow x^2 = \frac{-450}{2} < 0 \\
V = \varnothing \\ -----------------\)
- \(12x^2-94=8x^2+6 \\ \Leftrightarrow 12x^2-8x^2=6+94 \\
\Leftrightarrow 4x^2 = 100 \\
\Leftrightarrow x^2 = \frac{100}{4}=25 \\
\Leftrightarrow x = 5 \vee x = -5 \\
V = \Big\{-5, 5 \Big\} \\ -----------------\)
- \(-8x^2+1352=0 \\
\Leftrightarrow -8x^2 = -1352 \\
\Leftrightarrow x^2 = \frac{-1352}{-8}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(3x^2-3=0 \\
\Leftrightarrow 3x^2 = 3 \\
\Leftrightarrow x^2 = \frac{3}{3}=1 \\
\Leftrightarrow x = 1 \vee x = -1 \\
V = \Big\{-1, 1 \Big\} \\ -----------------\)
- \(-7x^2+0=0 \\
\Leftrightarrow -7x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-7}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(10x^2+263=6x^2+7 \\ \Leftrightarrow 10x^2-6x^2=7-263 \\
\Leftrightarrow 4x^2 = -256 \\
\Leftrightarrow x^2 = \frac{-256}{4} < 0 \\
V = \varnothing \\ -----------------\)
- \(4x^2-900=0 \\
\Leftrightarrow 4x^2 = 900 \\
\Leftrightarrow x^2 = \frac{900}{4}=225 \\
\Leftrightarrow x = 15 \vee x = -15 \\
V = \Big\{-15, 15 \Big\} \\ -----------------\)
- \(-3(9x^2+6)=-(20x^2-45) \\ \Leftrightarrow -27x^2-18=-20x^2+45 \\
\Leftrightarrow -27x^2+20x^2=45+18 \\
\Leftrightarrow -7x^2 = 63 \\
\Leftrightarrow x^2 = \frac{63}{-7} < 0 \\
V = \varnothing \\ -----------------\)