Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(4x^2+331=6x^2-7\)
- \(-6x^2+384=0\)
- \(3(8x^2-3)=-(-17x^2+856)\)
- \(4x^2-157=7x^2-10\)
- \(8x^2+8=0\)
- \(6x^2-384=0\)
- \(6x^2-486=0\)
- \(5x^2-5=0\)
- \(-3(2x^2+10)=-(10x^2-6)\)
- \(x^2-49=0\)
- \(3x^2-192=0\)
- \(-5(-2x^2+6)=-(-3x^2+30)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(4x^2+331=6x^2-7 \\ \Leftrightarrow 4x^2-6x^2=-7-331 \\
\Leftrightarrow -2x^2 = -338 \\
\Leftrightarrow x^2 = \frac{-338}{-2}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(-6x^2+384=0 \\
\Leftrightarrow -6x^2 = -384 \\
\Leftrightarrow x^2 = \frac{-384}{-6}=64 \\
\Leftrightarrow x = 8 \vee x = -8 \\
V = \Big\{-8, 8 \Big\} \\ -----------------\)
- \(3(8x^2-3)=-(-17x^2+856) \\ \Leftrightarrow 24x^2-9=17x^2-856 \\
\Leftrightarrow 24x^2-17x^2=-856+9 \\
\Leftrightarrow 7x^2 = -847 \\
\Leftrightarrow x^2 = \frac{-847}{7} < 0 \\
V = \varnothing \\ -----------------\)
- \(4x^2-157=7x^2-10 \\ \Leftrightarrow 4x^2-7x^2=-10+157 \\
\Leftrightarrow -3x^2 = 147 \\
\Leftrightarrow x^2 = \frac{147}{-3} < 0 \\
V = \varnothing \\ -----------------\)
- \(8x^2+8=0 \\
\Leftrightarrow 8x^2 = -8 \\
\Leftrightarrow x^2 = \frac{-8}{8} < 0 \\
V = \varnothing \\ -----------------\)
- \(6x^2-384=0 \\
\Leftrightarrow 6x^2 = 384 \\
\Leftrightarrow x^2 = \frac{384}{6}=64 \\
\Leftrightarrow x = 8 \vee x = -8 \\
V = \Big\{-8, 8 \Big\} \\ -----------------\)
- \(6x^2-486=0 \\
\Leftrightarrow 6x^2 = 486 \\
\Leftrightarrow x^2 = \frac{486}{6}=81 \\
\Leftrightarrow x = 9 \vee x = -9 \\
V = \Big\{-9, 9 \Big\} \\ -----------------\)
- \(5x^2-5=0 \\
\Leftrightarrow 5x^2 = 5 \\
\Leftrightarrow x^2 = \frac{5}{5}=1 \\
\Leftrightarrow x = 1 \vee x = -1 \\
V = \Big\{-1, 1 \Big\} \\ -----------------\)
- \(-3(2x^2+10)=-(10x^2-6) \\ \Leftrightarrow -6x^2-30=-10x^2+6 \\
\Leftrightarrow -6x^2+10x^2=6+30 \\
\Leftrightarrow 4x^2 = 36 \\
\Leftrightarrow x^2 = \frac{36}{4}=9 \\
\Leftrightarrow x = 3 \vee x = -3 \\
V = \Big\{-3, 3 \Big\} \\ -----------------\)
- \(x^2-49=0 \\
\Leftrightarrow x^2 = 49 \\
\Leftrightarrow x^2 = \frac{49}{1}=49 \\
\Leftrightarrow x = 7 \vee x = -7 \\
V = \Big\{-7, 7 \Big\} \\ -----------------\)
- \(3x^2-192=0 \\
\Leftrightarrow 3x^2 = 192 \\
\Leftrightarrow x^2 = \frac{192}{3}=64 \\
\Leftrightarrow x = 8 \vee x = -8 \\
V = \Big\{-8, 8 \Big\} \\ -----------------\)
- \(-5(-2x^2+6)=-(-3x^2+30) \\ \Leftrightarrow 10x^2-30=3x^2-30 \\
\Leftrightarrow 10x^2-3x^2=-30+30 \\
\Leftrightarrow 7x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{7}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)