Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(-4(6x^2+2x)=-(29x^2-9x)\)
- \(x^2-8x=7x^2-6x\)
- \(13x^2-22x=10x^2-3x\)
- \(2(-3x^2-10x)=-(x^2+21x)\)
- \(-2x^2+13x=0\)
- \(-2x^2-24x=-7x^2-4x\)
- \(-3x^2-17x=-6x^2-4x\)
- \(3x^2+6x=0\)
- \(-5x^2+11x=0\)
- \(3(-8x^2+9x)=-(26x^2-32x)\)
- \(-2x^2-15x=-4x^2+6x\)
- \(-4(5x^2-6x)=-(27x^2-40x)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(-4(6x^2+2x)=-(29x^2-9x) \\ \Leftrightarrow -24x^2-8x=-29x^2+9x \\
\Leftrightarrow -24x^2-8x+29x^2-9x= 0 \\
\Leftrightarrow 5x^2+17x=0 \\
\Leftrightarrow x(5x+17) = 0 \\
\Leftrightarrow x = 0 \vee 5x+17=0 \\
\Leftrightarrow x = 0 \vee x = \frac{-17}{5} \\ V = \Big\{ 0 ; \frac{-17}{5} \Big\} \\ -----------------\)
- \(x^2-8x=7x^2-6x \\ \Leftrightarrow -6x^2-2x=0 \\
\Leftrightarrow x(-6x-2) = 0 \\
\Leftrightarrow x = 0 \vee -6x-2=0 \\
\Leftrightarrow x = 0 \vee x = \frac{2}{-6} = \frac{-1}{3} \\ V = \Big\{ 0 ; \frac{-1}{3} \Big\} \\ -----------------\)
- \(13x^2-22x=10x^2-3x \\ \Leftrightarrow 3x^2-19x=0 \\
\Leftrightarrow x(3x-19) = 0 \\
\Leftrightarrow x = 0 \vee 3x-19=0 \\
\Leftrightarrow x = 0 \vee x = \frac{19}{3} \\ V = \Big\{ \frac{19}{3}; 0 \Big\} \\ -----------------\)
- \(2(-3x^2-10x)=-(x^2+21x) \\ \Leftrightarrow -6x^2-20x=-x^2-21x \\
\Leftrightarrow -6x^2-20x+x^2+21x= 0 \\
\Leftrightarrow -5x^2-1x=0 \\
\Leftrightarrow x(-5x-1) = 0 \\
\Leftrightarrow x = 0 \vee -5x-1=0 \\
\Leftrightarrow x = 0 \vee x = \frac{1}{-5} = \frac{-1}{5} \\ V = \Big\{ 0 ; \frac{-1}{5} \Big\} \\ -----------------\)
- \(-2x^2+13x=0 \\
\Leftrightarrow x(-2x+13) = 0 \\
\Leftrightarrow x = 0 \vee -2x+13=0 \\
\Leftrightarrow x = 0 \vee x = \frac{-13}{-2} = \frac{13}{2} \\ V = \Big\{ \frac{13}{2}; 0 \Big\} \\ -----------------\)
- \(-2x^2-24x=-7x^2-4x \\ \Leftrightarrow 5x^2-20x=0 \\
\Leftrightarrow x(5x-20) = 0 \\
\Leftrightarrow x = 0 \vee 5x-20=0 \\
\Leftrightarrow x = 0 \vee x = \frac{20}{5} = 4 \\ V = \Big\{ 4; 0 \Big\} \\ -----------------\)
- \(-3x^2-17x=-6x^2-4x \\ \Leftrightarrow 3x^2-13x=0 \\
\Leftrightarrow x(3x-13) = 0 \\
\Leftrightarrow x = 0 \vee 3x-13=0 \\
\Leftrightarrow x = 0 \vee x = \frac{13}{3} \\ V = \Big\{ \frac{13}{3}; 0 \Big\} \\ -----------------\)
- \(3x^2+6x=0 \\
\Leftrightarrow x(3x+6) = 0 \\
\Leftrightarrow x = 0 \vee 3x+6=0 \\
\Leftrightarrow x = 0 \vee x = \frac{-6}{3} = -2 \\ V = \Big\{ 0 ; -2 \Big\} \\ -----------------\)
- \(-5x^2+11x=0 \\
\Leftrightarrow x(-5x+11) = 0 \\
\Leftrightarrow x = 0 \vee -5x+11=0 \\
\Leftrightarrow x = 0 \vee x = \frac{-11}{-5} = \frac{11}{5} \\ V = \Big\{ \frac{11}{5}; 0 \Big\} \\ -----------------\)
- \(3(-8x^2+9x)=-(26x^2-32x) \\ \Leftrightarrow -24x^2+27x=-26x^2+32x \\
\Leftrightarrow -24x^2+27x+26x^2-32x= 0 \\
\Leftrightarrow 2x^2+5x=0 \\
\Leftrightarrow x(2x+5) = 0 \\
\Leftrightarrow x = 0 \vee 2x+5=0 \\
\Leftrightarrow x = 0 \vee x = \frac{-5}{2} \\ V = \Big\{ 0 ; \frac{-5}{2} \Big\} \\ -----------------\)
- \(-2x^2-15x=-4x^2+6x \\ \Leftrightarrow 2x^2-21x=0 \\
\Leftrightarrow x(2x-21) = 0 \\
\Leftrightarrow x = 0 \vee 2x-21=0 \\
\Leftrightarrow x = 0 \vee x = \frac{21}{2} \\ V = \Big\{ \frac{21}{2}; 0 \Big\} \\ -----------------\)
- \(-4(5x^2-6x)=-(27x^2-40x) \\ \Leftrightarrow -20x^2+24x=-27x^2+40x \\
\Leftrightarrow -20x^2+24x+27x^2-40x= 0 \\
\Leftrightarrow 7x^2+16x=0 \\
\Leftrightarrow x(7x+16) = 0 \\
\Leftrightarrow x = 0 \vee 7x+16=0 \\
\Leftrightarrow x = 0 \vee x = \frac{-16}{7} \\ V = \Big\{ 0 ; \frac{-16}{7} \Big\} \\ -----------------\)