Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(2x^2-651=-6x^2-3\)
- \(-12x^2+138=-4x^2+10\)
- \(-3(-8x^2+8)=-(-25x^2-201)\)
- \(9x^2-24=4x^2-4\)
- \(-3(4x^2+6)=-(6x^2+744)\)
- \(x^2+242=6x^2-3\)
- \(-2(9x^2-9)=-(17x^2+126)\)
- \(12x^2-2=9x^2-5\)
- \(12x^2-2=5x^2+5\)
- \(-4x^2-2=-10x^2-2\)
- \(-2x^2+338=0\)
- \(-5(7x^2+9)=-(30x^2+650)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(2x^2-651=-6x^2-3 \\ \Leftrightarrow 2x^2+6x^2=-3+651 \\
\Leftrightarrow 8x^2 = 648 \\
\Leftrightarrow x^2 = \frac{648}{8}=81 \\
\Leftrightarrow x = 9 \vee x = -9 \\
V = \Big\{-9, 9 \Big\} \\ -----------------\)
- \(-12x^2+138=-4x^2+10 \\ \Leftrightarrow -12x^2+4x^2=10-138 \\
\Leftrightarrow -8x^2 = -128 \\
\Leftrightarrow x^2 = \frac{-128}{-8}=16 \\
\Leftrightarrow x = 4 \vee x = -4 \\
V = \Big\{-4, 4 \Big\} \\ -----------------\)
- \(-3(-8x^2+8)=-(-25x^2-201) \\ \Leftrightarrow 24x^2-24=25x^2+201 \\
\Leftrightarrow 24x^2-25x^2=201+24 \\
\Leftrightarrow -x^2 = 225 \\
\Leftrightarrow x^2 = \frac{225}{-1} < 0 \\
V = \varnothing \\ -----------------\)
- \(9x^2-24=4x^2-4 \\ \Leftrightarrow 9x^2-4x^2=-4+24 \\
\Leftrightarrow 5x^2 = 20 \\
\Leftrightarrow x^2 = \frac{20}{5}=4 \\
\Leftrightarrow x = 2 \vee x = -2 \\
V = \Big\{-2, 2 \Big\} \\ -----------------\)
- \(-3(4x^2+6)=-(6x^2+744) \\ \Leftrightarrow -12x^2-18=-6x^2-744 \\
\Leftrightarrow -12x^2+6x^2=-744+18 \\
\Leftrightarrow -6x^2 = -726 \\
\Leftrightarrow x^2 = \frac{-726}{-6}=121 \\
\Leftrightarrow x = 11 \vee x = -11 \\
V = \Big\{-11, 11 \Big\} \\ -----------------\)
- \(x^2+242=6x^2-3 \\ \Leftrightarrow x^2-6x^2=-3-242 \\
\Leftrightarrow -5x^2 = -245 \\
\Leftrightarrow x^2 = \frac{-245}{-5}=49 \\
\Leftrightarrow x = 7 \vee x = -7 \\
V = \Big\{-7, 7 \Big\} \\ -----------------\)
- \(-2(9x^2-9)=-(17x^2+126) \\ \Leftrightarrow -18x^2+18=-17x^2-126 \\
\Leftrightarrow -18x^2+17x^2=-126-18 \\
\Leftrightarrow -x^2 = -144 \\
\Leftrightarrow x^2 = \frac{-144}{-1}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)
- \(12x^2-2=9x^2-5 \\ \Leftrightarrow 12x^2-9x^2=-5+2 \\
\Leftrightarrow 3x^2 = -3 \\
\Leftrightarrow x^2 = \frac{-3}{3} < 0 \\
V = \varnothing \\ -----------------\)
- \(12x^2-2=5x^2+5 \\ \Leftrightarrow 12x^2-5x^2=5+2 \\
\Leftrightarrow 7x^2 = 7 \\
\Leftrightarrow x^2 = \frac{7}{7}=1 \\
\Leftrightarrow x = 1 \vee x = -1 \\
V = \Big\{-1, 1 \Big\} \\ -----------------\)
- \(-4x^2-2=-10x^2-2 \\ \Leftrightarrow -4x^2+10x^2=-2+2 \\
\Leftrightarrow 6x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{6}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-2x^2+338=0 \\
\Leftrightarrow -2x^2 = -338 \\
\Leftrightarrow x^2 = \frac{-338}{-2}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(-5(7x^2+9)=-(30x^2+650) \\ \Leftrightarrow -35x^2-45=-30x^2-650 \\
\Leftrightarrow -35x^2+30x^2=-650+45 \\
\Leftrightarrow -5x^2 = -605 \\
\Leftrightarrow x^2 = \frac{-605}{-5}=121 \\
\Leftrightarrow x = 11 \vee x = -11 \\
V = \Big\{-11, 11 \Big\} \\ -----------------\)