Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(-3(10x^2+3)=-(34x^2-891)\)
- \(-2(4x^2-10)=-(11x^2+88)\)
- \(x^2+43=-4x^2-2\)
- \(2(-7x^2+5)=-(18x^2+474)\)
- \(2(-6x^2+6)=-(5x^2+1563)\)
- \(-2x^2+0=0\)
- \(-3(6x^2+4)=-(26x^2+980)\)
- \(-5(2x^2+4)=-(18x^2+20)\)
- \(5(-10x^2-4)=-(56x^2+44)\)
- \(5x^2-195=8x^2-3\)
- \(2(4x^2-5)=-(-14x^2+610)\)
- \(-10x^2-91=-8x^2+7\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(-3(10x^2+3)=-(34x^2-891) \\ \Leftrightarrow -30x^2-9=-34x^2+891 \\
\Leftrightarrow -30x^2+34x^2=891+9 \\
\Leftrightarrow 4x^2 = 900 \\
\Leftrightarrow x^2 = \frac{900}{4}=225 \\
\Leftrightarrow x = 15 \vee x = -15 \\
V = \Big\{-15, 15 \Big\} \\ -----------------\)
- \(-2(4x^2-10)=-(11x^2+88) \\ \Leftrightarrow -8x^2+20=-11x^2-88 \\
\Leftrightarrow -8x^2+11x^2=-88-20 \\
\Leftrightarrow 3x^2 = -108 \\
\Leftrightarrow x^2 = \frac{-108}{3} < 0 \\
V = \varnothing \\ -----------------\)
- \(x^2+43=-4x^2-2 \\ \Leftrightarrow x^2+4x^2=-2-43 \\
\Leftrightarrow 5x^2 = -45 \\
\Leftrightarrow x^2 = \frac{-45}{5} < 0 \\
V = \varnothing \\ -----------------\)
- \(2(-7x^2+5)=-(18x^2+474) \\ \Leftrightarrow -14x^2+10=-18x^2-474 \\
\Leftrightarrow -14x^2+18x^2=-474-10 \\
\Leftrightarrow 4x^2 = -484 \\
\Leftrightarrow x^2 = \frac{-484}{4} < 0 \\
V = \varnothing \\ -----------------\)
- \(2(-6x^2+6)=-(5x^2+1563) \\ \Leftrightarrow -12x^2+12=-5x^2-1563 \\
\Leftrightarrow -12x^2+5x^2=-1563-12 \\
\Leftrightarrow -7x^2 = -1575 \\
\Leftrightarrow x^2 = \frac{-1575}{-7}=225 \\
\Leftrightarrow x = 15 \vee x = -15 \\
V = \Big\{-15, 15 \Big\} \\ -----------------\)
- \(-2x^2+0=0 \\
\Leftrightarrow -2x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-2}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-3(6x^2+4)=-(26x^2+980) \\ \Leftrightarrow -18x^2-12=-26x^2-980 \\
\Leftrightarrow -18x^2+26x^2=-980+12 \\
\Leftrightarrow 8x^2 = -968 \\
\Leftrightarrow x^2 = \frac{-968}{8} < 0 \\
V = \varnothing \\ -----------------\)
- \(-5(2x^2+4)=-(18x^2+20) \\ \Leftrightarrow -10x^2-20=-18x^2-20 \\
\Leftrightarrow -10x^2+18x^2=-20+20 \\
\Leftrightarrow 8x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{8}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(5(-10x^2-4)=-(56x^2+44) \\ \Leftrightarrow -50x^2-20=-56x^2-44 \\
\Leftrightarrow -50x^2+56x^2=-44+20 \\
\Leftrightarrow 6x^2 = -24 \\
\Leftrightarrow x^2 = \frac{-24}{6} < 0 \\
V = \varnothing \\ -----------------\)
- \(5x^2-195=8x^2-3 \\ \Leftrightarrow 5x^2-8x^2=-3+195 \\
\Leftrightarrow -3x^2 = 192 \\
\Leftrightarrow x^2 = \frac{192}{-3} < 0 \\
V = \varnothing \\ -----------------\)
- \(2(4x^2-5)=-(-14x^2+610) \\ \Leftrightarrow 8x^2-10=14x^2-610 \\
\Leftrightarrow 8x^2-14x^2=-610+10 \\
\Leftrightarrow -6x^2 = -600 \\
\Leftrightarrow x^2 = \frac{-600}{-6}=100 \\
\Leftrightarrow x = 10 \vee x = -10 \\
V = \Big\{-10, 10 \Big\} \\ -----------------\)
- \(-10x^2-91=-8x^2+7 \\ \Leftrightarrow -10x^2+8x^2=7+91 \\
\Leftrightarrow -2x^2 = 98 \\
\Leftrightarrow x^2 = \frac{98}{-2} < 0 \\
V = \varnothing \\ -----------------\)