Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(-3x^2+300=0\)
- \(8x^2+288=0\)
- \(3(6x^2-7)=-(-15x^2+9)\)
- \(6x^2-384=0\)
- \(2(-6x^2-2)=-(10x^2-238)\)
- \(6x^2-6=0\)
- \(6x^2-203=8x^2-3\)
- \(2x^2+0=0\)
- \(-5(-8x^2+5)=-(-38x^2+17)\)
- \(-6x^2+0=0\)
- \(-3x^2+136=-7x^2-8\)
- \(3x^2-75=0\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(-3x^2+300=0 \\
\Leftrightarrow -3x^2 = -300 \\
\Leftrightarrow x^2 = \frac{-300}{-3}=100 \\
\Leftrightarrow x = 10 \vee x = -10 \\
V = \Big\{-10, 10 \Big\} \\ -----------------\)
- \(8x^2+288=0 \\
\Leftrightarrow 8x^2 = -288 \\
\Leftrightarrow x^2 = \frac{-288}{8} < 0 \\
V = \varnothing \\ -----------------\)
- \(3(6x^2-7)=-(-15x^2+9) \\ \Leftrightarrow 18x^2-21=15x^2-9 \\
\Leftrightarrow 18x^2-15x^2=-9+21 \\
\Leftrightarrow 3x^2 = 12 \\
\Leftrightarrow x^2 = \frac{12}{3}=4 \\
\Leftrightarrow x = 2 \vee x = -2 \\
V = \Big\{-2, 2 \Big\} \\ -----------------\)
- \(6x^2-384=0 \\
\Leftrightarrow 6x^2 = 384 \\
\Leftrightarrow x^2 = \frac{384}{6}=64 \\
\Leftrightarrow x = 8 \vee x = -8 \\
V = \Big\{-8, 8 \Big\} \\ -----------------\)
- \(2(-6x^2-2)=-(10x^2-238) \\ \Leftrightarrow -12x^2-4=-10x^2+238 \\
\Leftrightarrow -12x^2+10x^2=238+4 \\
\Leftrightarrow -2x^2 = 242 \\
\Leftrightarrow x^2 = \frac{242}{-2} < 0 \\
V = \varnothing \\ -----------------\)
- \(6x^2-6=0 \\
\Leftrightarrow 6x^2 = 6 \\
\Leftrightarrow x^2 = \frac{6}{6}=1 \\
\Leftrightarrow x = 1 \vee x = -1 \\
V = \Big\{-1, 1 \Big\} \\ -----------------\)
- \(6x^2-203=8x^2-3 \\ \Leftrightarrow 6x^2-8x^2=-3+203 \\
\Leftrightarrow -2x^2 = 200 \\
\Leftrightarrow x^2 = \frac{200}{-2} < 0 \\
V = \varnothing \\ -----------------\)
- \(2x^2+0=0 \\
\Leftrightarrow 2x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{2}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-5(-8x^2+5)=-(-38x^2+17) \\ \Leftrightarrow 40x^2-25=38x^2-17 \\
\Leftrightarrow 40x^2-38x^2=-17+25 \\
\Leftrightarrow 2x^2 = 8 \\
\Leftrightarrow x^2 = \frac{8}{2}=4 \\
\Leftrightarrow x = 2 \vee x = -2 \\
V = \Big\{-2, 2 \Big\} \\ -----------------\)
- \(-6x^2+0=0 \\
\Leftrightarrow -6x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-6}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-3x^2+136=-7x^2-8 \\ \Leftrightarrow -3x^2+7x^2=-8-136 \\
\Leftrightarrow 4x^2 = -144 \\
\Leftrightarrow x^2 = \frac{-144}{4} < 0 \\
V = \varnothing \\ -----------------\)
- \(3x^2-75=0 \\
\Leftrightarrow 3x^2 = 75 \\
\Leftrightarrow x^2 = \frac{75}{3}=25 \\
\Leftrightarrow x = 5 \vee x = -5 \\
V = \Big\{-5, 5 \Big\} \\ -----------------\)