Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(5x^2+703=-2x^2+3\)
- \(3(-10x^2+6)=-(34x^2-418)\)
- \(-3(-3x^2+3)=-(-x^2-959)\)
- \(4(10x^2-8)=-(-37x^2-16)\)
- \(-5x^2+5=0\)
- \(-3x^2+692=4x^2-8\)
- \(-2(-10x^2-4)=-(-27x^2+1000)\)
- \(9x^2+93=10x^2-7\)
- \(-6x^2+0=0\)
- \(-10x^2+515=-7x^2+8\)
- \(2(10x^2+9)=-(-14x^2-618)\)
- \(x^2+49=0\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(5x^2+703=-2x^2+3 \\ \Leftrightarrow 5x^2+2x^2=3-703 \\
\Leftrightarrow 7x^2 = -700 \\
\Leftrightarrow x^2 = \frac{-700}{7} < 0 \\
V = \varnothing \\ -----------------\)
- \(3(-10x^2+6)=-(34x^2-418) \\ \Leftrightarrow -30x^2+18=-34x^2+418 \\
\Leftrightarrow -30x^2+34x^2=418-18 \\
\Leftrightarrow 4x^2 = 400 \\
\Leftrightarrow x^2 = \frac{400}{4}=100 \\
\Leftrightarrow x = 10 \vee x = -10 \\
V = \Big\{-10, 10 \Big\} \\ -----------------\)
- \(-3(-3x^2+3)=-(-x^2-959) \\ \Leftrightarrow 9x^2-9=x^2+959 \\
\Leftrightarrow 9x^2-x^2=959+9 \\
\Leftrightarrow 8x^2 = 968 \\
\Leftrightarrow x^2 = \frac{968}{8}=121 \\
\Leftrightarrow x = 11 \vee x = -11 \\
V = \Big\{-11, 11 \Big\} \\ -----------------\)
- \(4(10x^2-8)=-(-37x^2-16) \\ \Leftrightarrow 40x^2-32=37x^2+16 \\
\Leftrightarrow 40x^2-37x^2=16+32 \\
\Leftrightarrow 3x^2 = 48 \\
\Leftrightarrow x^2 = \frac{48}{3}=16 \\
\Leftrightarrow x = 4 \vee x = -4 \\
V = \Big\{-4, 4 \Big\} \\ -----------------\)
- \(-5x^2+5=0 \\
\Leftrightarrow -5x^2 = -5 \\
\Leftrightarrow x^2 = \frac{-5}{-5}=1 \\
\Leftrightarrow x = 1 \vee x = -1 \\
V = \Big\{-1, 1 \Big\} \\ -----------------\)
- \(-3x^2+692=4x^2-8 \\ \Leftrightarrow -3x^2-4x^2=-8-692 \\
\Leftrightarrow -7x^2 = -700 \\
\Leftrightarrow x^2 = \frac{-700}{-7}=100 \\
\Leftrightarrow x = 10 \vee x = -10 \\
V = \Big\{-10, 10 \Big\} \\ -----------------\)
- \(-2(-10x^2-4)=-(-27x^2+1000) \\ \Leftrightarrow 20x^2+8=27x^2-1000 \\
\Leftrightarrow 20x^2-27x^2=-1000-8 \\
\Leftrightarrow -7x^2 = -1008 \\
\Leftrightarrow x^2 = \frac{-1008}{-7}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)
- \(9x^2+93=10x^2-7 \\ \Leftrightarrow 9x^2-10x^2=-7-93 \\
\Leftrightarrow -x^2 = -100 \\
\Leftrightarrow x^2 = \frac{-100}{-1}=100 \\
\Leftrightarrow x = 10 \vee x = -10 \\
V = \Big\{-10, 10 \Big\} \\ -----------------\)
- \(-6x^2+0=0 \\
\Leftrightarrow -6x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-6}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-10x^2+515=-7x^2+8 \\ \Leftrightarrow -10x^2+7x^2=8-515 \\
\Leftrightarrow -3x^2 = -507 \\
\Leftrightarrow x^2 = \frac{-507}{-3}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(2(10x^2+9)=-(-14x^2-618) \\ \Leftrightarrow 20x^2+18=14x^2+618 \\
\Leftrightarrow 20x^2-14x^2=618-18 \\
\Leftrightarrow 6x^2 = 600 \\
\Leftrightarrow x^2 = \frac{600}{6}=100 \\
\Leftrightarrow x = 10 \vee x = -10 \\
V = \Big\{-10, 10 \Big\} \\ -----------------\)
- \(x^2+49=0 \\
\Leftrightarrow x^2 = -49 \\
\Leftrightarrow x^2 = \frac{-49}{1} < 0 \\
V = \varnothing \\ -----------------\)