Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(-4(-6x^2+4)=-(-22x^2-376)\)
- \(-5x^2+980=0\)
- \(-4(5x^2-10)=-(24x^2-296)\)
- \(2x^2+338=0\)
- \(-5x^2+125=0\)
- \(-3(4x^2+5)=-(20x^2+15)\)
- \(-7x^2+1183=0\)
- \(2x^2+198=4x^2-2\)
- \(-3(6x^2+4)=-(15x^2+600)\)
- \(5(-3x^2-7)=-(23x^2+43)\)
- \(-3(8x^2-2)=-(28x^2+250)\)
- \(4(10x^2-6)=-(-32x^2+1376)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(-4(-6x^2+4)=-(-22x^2-376) \\ \Leftrightarrow 24x^2-16=22x^2+376 \\
\Leftrightarrow 24x^2-22x^2=376+16 \\
\Leftrightarrow 2x^2 = 392 \\
\Leftrightarrow x^2 = \frac{392}{2}=196 \\
\Leftrightarrow x = 14 \vee x = -14 \\
V = \Big\{-14, 14 \Big\} \\ -----------------\)
- \(-5x^2+980=0 \\
\Leftrightarrow -5x^2 = -980 \\
\Leftrightarrow x^2 = \frac{-980}{-5}=196 \\
\Leftrightarrow x = 14 \vee x = -14 \\
V = \Big\{-14, 14 \Big\} \\ -----------------\)
- \(-4(5x^2-10)=-(24x^2-296) \\ \Leftrightarrow -20x^2+40=-24x^2+296 \\
\Leftrightarrow -20x^2+24x^2=296-40 \\
\Leftrightarrow 4x^2 = 256 \\
\Leftrightarrow x^2 = \frac{256}{4}=64 \\
\Leftrightarrow x = 8 \vee x = -8 \\
V = \Big\{-8, 8 \Big\} \\ -----------------\)
- \(2x^2+338=0 \\
\Leftrightarrow 2x^2 = -338 \\
\Leftrightarrow x^2 = \frac{-338}{2} < 0 \\
V = \varnothing \\ -----------------\)
- \(-5x^2+125=0 \\
\Leftrightarrow -5x^2 = -125 \\
\Leftrightarrow x^2 = \frac{-125}{-5}=25 \\
\Leftrightarrow x = 5 \vee x = -5 \\
V = \Big\{-5, 5 \Big\} \\ -----------------\)
- \(-3(4x^2+5)=-(20x^2+15) \\ \Leftrightarrow -12x^2-15=-20x^2-15 \\
\Leftrightarrow -12x^2+20x^2=-15+15 \\
\Leftrightarrow 8x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{8}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-7x^2+1183=0 \\
\Leftrightarrow -7x^2 = -1183 \\
\Leftrightarrow x^2 = \frac{-1183}{-7}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(2x^2+198=4x^2-2 \\ \Leftrightarrow 2x^2-4x^2=-2-198 \\
\Leftrightarrow -2x^2 = -200 \\
\Leftrightarrow x^2 = \frac{-200}{-2}=100 \\
\Leftrightarrow x = 10 \vee x = -10 \\
V = \Big\{-10, 10 \Big\} \\ -----------------\)
- \(-3(6x^2+4)=-(15x^2+600) \\ \Leftrightarrow -18x^2-12=-15x^2-600 \\
\Leftrightarrow -18x^2+15x^2=-600+12 \\
\Leftrightarrow -3x^2 = -588 \\
\Leftrightarrow x^2 = \frac{-588}{-3}=196 \\
\Leftrightarrow x = 14 \vee x = -14 \\
V = \Big\{-14, 14 \Big\} \\ -----------------\)
- \(5(-3x^2-7)=-(23x^2+43) \\ \Leftrightarrow -15x^2-35=-23x^2-43 \\
\Leftrightarrow -15x^2+23x^2=-43+35 \\
\Leftrightarrow 8x^2 = -8 \\
\Leftrightarrow x^2 = \frac{-8}{8} < 0 \\
V = \varnothing \\ -----------------\)
- \(-3(8x^2-2)=-(28x^2+250) \\ \Leftrightarrow -24x^2+6=-28x^2-250 \\
\Leftrightarrow -24x^2+28x^2=-250-6 \\
\Leftrightarrow 4x^2 = -256 \\
\Leftrightarrow x^2 = \frac{-256}{4} < 0 \\
V = \varnothing \\ -----------------\)
- \(4(10x^2-6)=-(-32x^2+1376) \\ \Leftrightarrow 40x^2-24=32x^2-1376 \\
\Leftrightarrow 40x^2-32x^2=-1376+24 \\
\Leftrightarrow 8x^2 = -1352 \\
\Leftrightarrow x^2 = \frac{-1352}{8} < 0 \\
V = \varnothing \\ -----------------\)