Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(2x^2-200=0\)
- \(-5(4x^2-5)=-(26x^2+29)\)
- \(10x^2-58=3x^2+5\)
- \(7x^2-607=2x^2-2\)
- \(-7x^2-255=-2x^2-10\)
- \(3(-7x^2-8)=-(20x^2+49)\)
- \(-2(5x^2+8)=-(17x^2-96)\)
- \(-8x^2+6=-3x^2+6\)
- \(4x^2-774=8x^2+10\)
- \(-8x^2+1568=0\)
- \(2(7x^2+6)=-(-22x^2+1340)\)
- \(-6x^2+2=2x^2+2\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(2x^2-200=0 \\
\Leftrightarrow 2x^2 = 200 \\
\Leftrightarrow x^2 = \frac{200}{2}=100 \\
\Leftrightarrow x = 10 \vee x = -10 \\
V = \Big\{-10, 10 \Big\} \\ -----------------\)
- \(-5(4x^2-5)=-(26x^2+29) \\ \Leftrightarrow -20x^2+25=-26x^2-29 \\
\Leftrightarrow -20x^2+26x^2=-29-25 \\
\Leftrightarrow 6x^2 = -54 \\
\Leftrightarrow x^2 = \frac{-54}{6} < 0 \\
V = \varnothing \\ -----------------\)
- \(10x^2-58=3x^2+5 \\ \Leftrightarrow 10x^2-3x^2=5+58 \\
\Leftrightarrow 7x^2 = 63 \\
\Leftrightarrow x^2 = \frac{63}{7}=9 \\
\Leftrightarrow x = 3 \vee x = -3 \\
V = \Big\{-3, 3 \Big\} \\ -----------------\)
- \(7x^2-607=2x^2-2 \\ \Leftrightarrow 7x^2-2x^2=-2+607 \\
\Leftrightarrow 5x^2 = 605 \\
\Leftrightarrow x^2 = \frac{605}{5}=121 \\
\Leftrightarrow x = 11 \vee x = -11 \\
V = \Big\{-11, 11 \Big\} \\ -----------------\)
- \(-7x^2-255=-2x^2-10 \\ \Leftrightarrow -7x^2+2x^2=-10+255 \\
\Leftrightarrow -5x^2 = 245 \\
\Leftrightarrow x^2 = \frac{245}{-5} < 0 \\
V = \varnothing \\ -----------------\)
- \(3(-7x^2-8)=-(20x^2+49) \\ \Leftrightarrow -21x^2-24=-20x^2-49 \\
\Leftrightarrow -21x^2+20x^2=-49+24 \\
\Leftrightarrow -x^2 = -25 \\
\Leftrightarrow x^2 = \frac{-25}{-1}=25 \\
\Leftrightarrow x = 5 \vee x = -5 \\
V = \Big\{-5, 5 \Big\} \\ -----------------\)
- \(-2(5x^2+8)=-(17x^2-96) \\ \Leftrightarrow -10x^2-16=-17x^2+96 \\
\Leftrightarrow -10x^2+17x^2=96+16 \\
\Leftrightarrow 7x^2 = 112 \\
\Leftrightarrow x^2 = \frac{112}{7}=16 \\
\Leftrightarrow x = 4 \vee x = -4 \\
V = \Big\{-4, 4 \Big\} \\ -----------------\)
- \(-8x^2+6=-3x^2+6 \\ \Leftrightarrow -8x^2+3x^2=6-6 \\
\Leftrightarrow -5x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-5}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(4x^2-774=8x^2+10 \\ \Leftrightarrow 4x^2-8x^2=10+774 \\
\Leftrightarrow -4x^2 = 784 \\
\Leftrightarrow x^2 = \frac{784}{-4} < 0 \\
V = \varnothing \\ -----------------\)
- \(-8x^2+1568=0 \\
\Leftrightarrow -8x^2 = -1568 \\
\Leftrightarrow x^2 = \frac{-1568}{-8}=196 \\
\Leftrightarrow x = 14 \vee x = -14 \\
V = \Big\{-14, 14 \Big\} \\ -----------------\)
- \(2(7x^2+6)=-(-22x^2+1340) \\ \Leftrightarrow 14x^2+12=22x^2-1340 \\
\Leftrightarrow 14x^2-22x^2=-1340-12 \\
\Leftrightarrow -8x^2 = -1352 \\
\Leftrightarrow x^2 = \frac{-1352}{-8}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(-6x^2+2=2x^2+2 \\ \Leftrightarrow -6x^2-2x^2=2-2 \\
\Leftrightarrow -8x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-8}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)