Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(6x^2-1176=0\)
- \(-4(-10x^2-9)=-(-36x^2-100)\)
- \(-3x^2-1014=-10x^2-6\)
- \(x^2+0=0\)
- \(7x^2+448=0\)
- \(-8x^2-1568=0\)
- \(3x^2+90=4x^2-10\)
- \(-5(6x^2-7)=-(34x^2+221)\)
- \(2x^2-338=0\)
- \(-3(-5x^2+6)=-(-8x^2-829)\)
- \(2x^2-6=8x^2-6\)
- \(6x^2-579=2x^2-3\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(6x^2-1176=0 \\
\Leftrightarrow 6x^2 = 1176 \\
\Leftrightarrow x^2 = \frac{1176}{6}=196 \\
\Leftrightarrow x = 14 \vee x = -14 \\
V = \Big\{-14, 14 \Big\} \\ -----------------\)
- \(-4(-10x^2-9)=-(-36x^2-100) \\ \Leftrightarrow 40x^2+36=36x^2+100 \\
\Leftrightarrow 40x^2-36x^2=100-36 \\
\Leftrightarrow 4x^2 = 64 \\
\Leftrightarrow x^2 = \frac{64}{4}=16 \\
\Leftrightarrow x = 4 \vee x = -4 \\
V = \Big\{-4, 4 \Big\} \\ -----------------\)
- \(-3x^2-1014=-10x^2-6 \\ \Leftrightarrow -3x^2+10x^2=-6+1014 \\
\Leftrightarrow 7x^2 = 1008 \\
\Leftrightarrow x^2 = \frac{1008}{7}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)
- \(x^2+0=0 \\
\Leftrightarrow x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{1}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(7x^2+448=0 \\
\Leftrightarrow 7x^2 = -448 \\
\Leftrightarrow x^2 = \frac{-448}{7} < 0 \\
V = \varnothing \\ -----------------\)
- \(-8x^2-1568=0 \\
\Leftrightarrow -8x^2 = 1568 \\
\Leftrightarrow x^2 = \frac{1568}{-8} < 0 \\
V = \varnothing \\ -----------------\)
- \(3x^2+90=4x^2-10 \\ \Leftrightarrow 3x^2-4x^2=-10-90 \\
\Leftrightarrow -x^2 = -100 \\
\Leftrightarrow x^2 = \frac{-100}{-1}=100 \\
\Leftrightarrow x = 10 \vee x = -10 \\
V = \Big\{-10, 10 \Big\} \\ -----------------\)
- \(-5(6x^2-7)=-(34x^2+221) \\ \Leftrightarrow -30x^2+35=-34x^2-221 \\
\Leftrightarrow -30x^2+34x^2=-221-35 \\
\Leftrightarrow 4x^2 = -256 \\
\Leftrightarrow x^2 = \frac{-256}{4} < 0 \\
V = \varnothing \\ -----------------\)
- \(2x^2-338=0 \\
\Leftrightarrow 2x^2 = 338 \\
\Leftrightarrow x^2 = \frac{338}{2}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(-3(-5x^2+6)=-(-8x^2-829) \\ \Leftrightarrow 15x^2-18=8x^2+829 \\
\Leftrightarrow 15x^2-8x^2=829+18 \\
\Leftrightarrow 7x^2 = 847 \\
\Leftrightarrow x^2 = \frac{847}{7}=121 \\
\Leftrightarrow x = 11 \vee x = -11 \\
V = \Big\{-11, 11 \Big\} \\ -----------------\)
- \(2x^2-6=8x^2-6 \\ \Leftrightarrow 2x^2-8x^2=-6+6 \\
\Leftrightarrow -6x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-6}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(6x^2-579=2x^2-3 \\ \Leftrightarrow 6x^2-2x^2=-3+579 \\
\Leftrightarrow 4x^2 = 576 \\
\Leftrightarrow x^2 = \frac{576}{4}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)