Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(-x^2+0=0\)
- \(-4x^2+1132=-9x^2+7\)
- \(-7x^2+7=0\)
- \(4x^2+508=-4x^2-4\)
- \(-x^2+16=0\)
- \(-6x^2-96=0\)
- \(-2x^2+72=0\)
- \(-x^2-1342=-7x^2+8\)
- \(-3(-6x^2-10)=-(-15x^2+558)\)
- \(-4x^2+196=0\)
- \(13x^2+3=9x^2+3\)
- \(3(-4x^2+9)=-(17x^2-632)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(-x^2+0=0 \\
\Leftrightarrow -x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-1}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-4x^2+1132=-9x^2+7 \\ \Leftrightarrow -4x^2+9x^2=7-1132 \\
\Leftrightarrow 5x^2 = -1125 \\
\Leftrightarrow x^2 = \frac{-1125}{5} < 0 \\
V = \varnothing \\ -----------------\)
- \(-7x^2+7=0 \\
\Leftrightarrow -7x^2 = -7 \\
\Leftrightarrow x^2 = \frac{-7}{-7}=1 \\
\Leftrightarrow x = 1 \vee x = -1 \\
V = \Big\{-1, 1 \Big\} \\ -----------------\)
- \(4x^2+508=-4x^2-4 \\ \Leftrightarrow 4x^2+4x^2=-4-508 \\
\Leftrightarrow 8x^2 = -512 \\
\Leftrightarrow x^2 = \frac{-512}{8} < 0 \\
V = \varnothing \\ -----------------\)
- \(-x^2+16=0 \\
\Leftrightarrow -x^2 = -16 \\
\Leftrightarrow x^2 = \frac{-16}{-1}=16 \\
\Leftrightarrow x = 4 \vee x = -4 \\
V = \Big\{-4, 4 \Big\} \\ -----------------\)
- \(-6x^2-96=0 \\
\Leftrightarrow -6x^2 = 96 \\
\Leftrightarrow x^2 = \frac{96}{-6} < 0 \\
V = \varnothing \\ -----------------\)
- \(-2x^2+72=0 \\
\Leftrightarrow -2x^2 = -72 \\
\Leftrightarrow x^2 = \frac{-72}{-2}=36 \\
\Leftrightarrow x = 6 \vee x = -6 \\
V = \Big\{-6, 6 \Big\} \\ -----------------\)
- \(-x^2-1342=-7x^2+8 \\ \Leftrightarrow -x^2+7x^2=8+1342 \\
\Leftrightarrow 6x^2 = 1350 \\
\Leftrightarrow x^2 = \frac{1350}{6}=225 \\
\Leftrightarrow x = 15 \vee x = -15 \\
V = \Big\{-15, 15 \Big\} \\ -----------------\)
- \(-3(-6x^2-10)=-(-15x^2+558) \\ \Leftrightarrow 18x^2+30=15x^2-558 \\
\Leftrightarrow 18x^2-15x^2=-558-30 \\
\Leftrightarrow 3x^2 = -588 \\
\Leftrightarrow x^2 = \frac{-588}{3} < 0 \\
V = \varnothing \\ -----------------\)
- \(-4x^2+196=0 \\
\Leftrightarrow -4x^2 = -196 \\
\Leftrightarrow x^2 = \frac{-196}{-4}=49 \\
\Leftrightarrow x = 7 \vee x = -7 \\
V = \Big\{-7, 7 \Big\} \\ -----------------\)
- \(13x^2+3=9x^2+3 \\ \Leftrightarrow 13x^2-9x^2=3-3 \\
\Leftrightarrow 4x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{4}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(3(-4x^2+9)=-(17x^2-632) \\ \Leftrightarrow -12x^2+27=-17x^2+632 \\
\Leftrightarrow -12x^2+17x^2=632-27 \\
\Leftrightarrow 5x^2 = 605 \\
\Leftrightarrow x^2 = \frac{605}{5}=121 \\
\Leftrightarrow x = 11 \vee x = -11 \\
V = \Big\{-11, 11 \Big\} \\ -----------------\)