Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(4x^2-324=0\)
- \(11x^2-428=8x^2+4\)
- \(-x^2+16=0\)
- \(x^2-49=0\)
- \(-14x^2-249=-10x^2+7\)
- \(3(10x^2+8)=-(-37x^2+1159)\)
- \(5(3x^2+2)=-(-19x^2-14)\)
- \(-3(-3x^2+6)=-(-7x^2+10)\)
- \(-4(-2x^2+9)=-(-x^2-412)\)
- \(5(-5x^2-10)=-(29x^2-526)\)
- \(3(-2x^2+10)=-(14x^2-678)\)
- \(-4(-8x^2-4)=-(-39x^2-23)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(4x^2-324=0 \\
\Leftrightarrow 4x^2 = 324 \\
\Leftrightarrow x^2 = \frac{324}{4}=81 \\
\Leftrightarrow x = 9 \vee x = -9 \\
V = \Big\{-9, 9 \Big\} \\ -----------------\)
- \(11x^2-428=8x^2+4 \\ \Leftrightarrow 11x^2-8x^2=4+428 \\
\Leftrightarrow 3x^2 = 432 \\
\Leftrightarrow x^2 = \frac{432}{3}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)
- \(-x^2+16=0 \\
\Leftrightarrow -x^2 = -16 \\
\Leftrightarrow x^2 = \frac{-16}{-1}=16 \\
\Leftrightarrow x = 4 \vee x = -4 \\
V = \Big\{-4, 4 \Big\} \\ -----------------\)
- \(x^2-49=0 \\
\Leftrightarrow x^2 = 49 \\
\Leftrightarrow x^2 = \frac{49}{1}=49 \\
\Leftrightarrow x = 7 \vee x = -7 \\
V = \Big\{-7, 7 \Big\} \\ -----------------\)
- \(-14x^2-249=-10x^2+7 \\ \Leftrightarrow -14x^2+10x^2=7+249 \\
\Leftrightarrow -4x^2 = 256 \\
\Leftrightarrow x^2 = \frac{256}{-4} < 0 \\
V = \varnothing \\ -----------------\)
- \(3(10x^2+8)=-(-37x^2+1159) \\ \Leftrightarrow 30x^2+24=37x^2-1159 \\
\Leftrightarrow 30x^2-37x^2=-1159-24 \\
\Leftrightarrow -7x^2 = -1183 \\
\Leftrightarrow x^2 = \frac{-1183}{-7}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(5(3x^2+2)=-(-19x^2-14) \\ \Leftrightarrow 15x^2+10=19x^2+14 \\
\Leftrightarrow 15x^2-19x^2=14-10 \\
\Leftrightarrow -4x^2 = 4 \\
\Leftrightarrow x^2 = \frac{4}{-4} < 0 \\
V = \varnothing \\ -----------------\)
- \(-3(-3x^2+6)=-(-7x^2+10) \\ \Leftrightarrow 9x^2-18=7x^2-10 \\
\Leftrightarrow 9x^2-7x^2=-10+18 \\
\Leftrightarrow 2x^2 = 8 \\
\Leftrightarrow x^2 = \frac{8}{2}=4 \\
\Leftrightarrow x = 2 \vee x = -2 \\
V = \Big\{-2, 2 \Big\} \\ -----------------\)
- \(-4(-2x^2+9)=-(-x^2-412) \\ \Leftrightarrow 8x^2-36=x^2+412 \\
\Leftrightarrow 8x^2-x^2=412+36 \\
\Leftrightarrow 7x^2 = 448 \\
\Leftrightarrow x^2 = \frac{448}{7}=64 \\
\Leftrightarrow x = 8 \vee x = -8 \\
V = \Big\{-8, 8 \Big\} \\ -----------------\)
- \(5(-5x^2-10)=-(29x^2-526) \\ \Leftrightarrow -25x^2-50=-29x^2+526 \\
\Leftrightarrow -25x^2+29x^2=526+50 \\
\Leftrightarrow 4x^2 = 576 \\
\Leftrightarrow x^2 = \frac{576}{4}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)
- \(3(-2x^2+10)=-(14x^2-678) \\ \Leftrightarrow -6x^2+30=-14x^2+678 \\
\Leftrightarrow -6x^2+14x^2=678-30 \\
\Leftrightarrow 8x^2 = 648 \\
\Leftrightarrow x^2 = \frac{648}{8}=81 \\
\Leftrightarrow x = 9 \vee x = -9 \\
V = \Big\{-9, 9 \Big\} \\ -----------------\)
- \(-4(-8x^2-4)=-(-39x^2-23) \\ \Leftrightarrow 32x^2+16=39x^2+23 \\
\Leftrightarrow 32x^2-39x^2=23-16 \\
\Leftrightarrow -7x^2 = 7 \\
\Leftrightarrow x^2 = \frac{7}{-7} < 0 \\
V = \varnothing \\ -----------------\)