Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(-4x^2+718=2x^2-8\)
- \(-8x^2+385=-6x^2-7\)
- \(-4(-8x^2+7)=-(-31x^2+53)\)
- \(-2(5x^2+10)=-(6x^2+344)\)
- \(3(8x^2+2)=-(-17x^2-1189)\)
- \(-5x^2+180=0\)
- \(11x^2+6=10x^2-3\)
- \(5x^2-180=0\)
- \(6x^2+426=9x^2-6\)
- \(3(-2x^2-10)=-(2x^2+26)\)
- \(9x^2+3=7x^2+3\)
- \(-4(-10x^2+8)=-(-39x^2-4)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(-4x^2+718=2x^2-8 \\ \Leftrightarrow -4x^2-2x^2=-8-718 \\
\Leftrightarrow -6x^2 = -726 \\
\Leftrightarrow x^2 = \frac{-726}{-6}=121 \\
\Leftrightarrow x = 11 \vee x = -11 \\
V = \Big\{-11, 11 \Big\} \\ -----------------\)
- \(-8x^2+385=-6x^2-7 \\ \Leftrightarrow -8x^2+6x^2=-7-385 \\
\Leftrightarrow -2x^2 = -392 \\
\Leftrightarrow x^2 = \frac{-392}{-2}=196 \\
\Leftrightarrow x = 14 \vee x = -14 \\
V = \Big\{-14, 14 \Big\} \\ -----------------\)
- \(-4(-8x^2+7)=-(-31x^2+53) \\ \Leftrightarrow 32x^2-28=31x^2-53 \\
\Leftrightarrow 32x^2-31x^2=-53+28 \\
\Leftrightarrow x^2 = -25 \\
\Leftrightarrow x^2 = \frac{-25}{1} < 0 \\
V = \varnothing \\ -----------------\)
- \(-2(5x^2+10)=-(6x^2+344) \\ \Leftrightarrow -10x^2-20=-6x^2-344 \\
\Leftrightarrow -10x^2+6x^2=-344+20 \\
\Leftrightarrow -4x^2 = -324 \\
\Leftrightarrow x^2 = \frac{-324}{-4}=81 \\
\Leftrightarrow x = 9 \vee x = -9 \\
V = \Big\{-9, 9 \Big\} \\ -----------------\)
- \(3(8x^2+2)=-(-17x^2-1189) \\ \Leftrightarrow 24x^2+6=17x^2+1189 \\
\Leftrightarrow 24x^2-17x^2=1189-6 \\
\Leftrightarrow 7x^2 = 1183 \\
\Leftrightarrow x^2 = \frac{1183}{7}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(-5x^2+180=0 \\
\Leftrightarrow -5x^2 = -180 \\
\Leftrightarrow x^2 = \frac{-180}{-5}=36 \\
\Leftrightarrow x = 6 \vee x = -6 \\
V = \Big\{-6, 6 \Big\} \\ -----------------\)
- \(11x^2+6=10x^2-3 \\ \Leftrightarrow 11x^2-10x^2=-3-6 \\
\Leftrightarrow x^2 = -9 \\
\Leftrightarrow x^2 = \frac{-9}{1} < 0 \\
V = \varnothing \\ -----------------\)
- \(5x^2-180=0 \\
\Leftrightarrow 5x^2 = 180 \\
\Leftrightarrow x^2 = \frac{180}{5}=36 \\
\Leftrightarrow x = 6 \vee x = -6 \\
V = \Big\{-6, 6 \Big\} \\ -----------------\)
- \(6x^2+426=9x^2-6 \\ \Leftrightarrow 6x^2-9x^2=-6-426 \\
\Leftrightarrow -3x^2 = -432 \\
\Leftrightarrow x^2 = \frac{-432}{-3}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)
- \(3(-2x^2-10)=-(2x^2+26) \\ \Leftrightarrow -6x^2-30=-2x^2-26 \\
\Leftrightarrow -6x^2+2x^2=-26+30 \\
\Leftrightarrow -4x^2 = 4 \\
\Leftrightarrow x^2 = \frac{4}{-4} < 0 \\
V = \varnothing \\ -----------------\)
- \(9x^2+3=7x^2+3 \\ \Leftrightarrow 9x^2-7x^2=3-3 \\
\Leftrightarrow 2x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{2}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-4(-10x^2+8)=-(-39x^2-4) \\ \Leftrightarrow 40x^2-32=39x^2+4 \\
\Leftrightarrow 40x^2-39x^2=4+32 \\
\Leftrightarrow x^2 = 36 \\
\Leftrightarrow x^2 = \frac{36}{1}=36 \\
\Leftrightarrow x = 6 \vee x = -6 \\
V = \Big\{-6, 6 \Big\} \\ -----------------\)