Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(9x^2-178=8x^2-9\)
- \(-3(-5x^2+6)=-(-11x^2+214)\)
- \(-2(-8x^2-2)=-(-11x^2-4)\)
- \(-3x^2-300=0\)
- \(6x^2+216=0\)
- \(-2x^2-162=0\)
- \(4x^2-900=0\)
- \(x^2+4=0\)
- \(3(2x^2-4)=-(0x^2+1188)\)
- \(-3(6x^2+8)=-(25x^2+24)\)
- \(14x^2-1564=6x^2+4\)
- \(7x^2+1008=0\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(9x^2-178=8x^2-9 \\ \Leftrightarrow 9x^2-8x^2=-9+178 \\
\Leftrightarrow x^2 = 169 \\
\Leftrightarrow x^2 = \frac{169}{1}=169 \\
\Leftrightarrow x = 13 \vee x = -13 \\
V = \Big\{-13, 13 \Big\} \\ -----------------\)
- \(-3(-5x^2+6)=-(-11x^2+214) \\ \Leftrightarrow 15x^2-18=11x^2-214 \\
\Leftrightarrow 15x^2-11x^2=-214+18 \\
\Leftrightarrow 4x^2 = -196 \\
\Leftrightarrow x^2 = \frac{-196}{4} < 0 \\
V = \varnothing \\ -----------------\)
- \(-2(-8x^2-2)=-(-11x^2-4) \\ \Leftrightarrow 16x^2+4=11x^2+4 \\
\Leftrightarrow 16x^2-11x^2=4-4 \\
\Leftrightarrow 5x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{5}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-3x^2-300=0 \\
\Leftrightarrow -3x^2 = 300 \\
\Leftrightarrow x^2 = \frac{300}{-3} < 0 \\
V = \varnothing \\ -----------------\)
- \(6x^2+216=0 \\
\Leftrightarrow 6x^2 = -216 \\
\Leftrightarrow x^2 = \frac{-216}{6} < 0 \\
V = \varnothing \\ -----------------\)
- \(-2x^2-162=0 \\
\Leftrightarrow -2x^2 = 162 \\
\Leftrightarrow x^2 = \frac{162}{-2} < 0 \\
V = \varnothing \\ -----------------\)
- \(4x^2-900=0 \\
\Leftrightarrow 4x^2 = 900 \\
\Leftrightarrow x^2 = \frac{900}{4}=225 \\
\Leftrightarrow x = 15 \vee x = -15 \\
V = \Big\{-15, 15 \Big\} \\ -----------------\)
- \(x^2+4=0 \\
\Leftrightarrow x^2 = -4 \\
\Leftrightarrow x^2 = \frac{-4}{1} < 0 \\
V = \varnothing \\ -----------------\)
- \(3(2x^2-4)=-(0x^2+1188) \\ \Leftrightarrow 6x^2-12=0x^2-1188 \\
\Leftrightarrow 6x^2+0x^2=-1188+12 \\
\Leftrightarrow 6x^2 = -1176 \\
\Leftrightarrow x^2 = \frac{-1176}{6} < 0 \\
V = \varnothing \\ -----------------\)
- \(-3(6x^2+8)=-(25x^2+24) \\ \Leftrightarrow -18x^2-24=-25x^2-24 \\
\Leftrightarrow -18x^2+25x^2=-24+24 \\
\Leftrightarrow 7x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{7}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(14x^2-1564=6x^2+4 \\ \Leftrightarrow 14x^2-6x^2=4+1564 \\
\Leftrightarrow 8x^2 = 1568 \\
\Leftrightarrow x^2 = \frac{1568}{8}=196 \\
\Leftrightarrow x = 14 \vee x = -14 \\
V = \Big\{-14, 14 \Big\} \\ -----------------\)
- \(7x^2+1008=0 \\
\Leftrightarrow 7x^2 = -1008 \\
\Leftrightarrow x^2 = \frac{-1008}{7} < 0 \\
V = \varnothing \\ -----------------\)