Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(-4x^2-174=-9x^2+6\)
- \(-11x^2+283=-3x^2-5\)
- \(-x^2+0=0\)
- \(2x^2-570=-5x^2-3\)
- \(4x^2-9=6x^2+9\)
- \(4(-5x^2+4)=-(14x^2-232)\)
- \(5x^2+245=0\)
- \(-x^2-169=0\)
- \(-x^2+4=0\)
- \(7x^2-11=4x^2-8\)
- \(7x^2+700=0\)
- \(5(4x^2+4)=-(-13x^2-272)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(-4x^2-174=-9x^2+6 \\ \Leftrightarrow -4x^2+9x^2=6+174 \\
\Leftrightarrow 5x^2 = 180 \\
\Leftrightarrow x^2 = \frac{180}{5}=36 \\
\Leftrightarrow x = 6 \vee x = -6 \\
V = \Big\{-6, 6 \Big\} \\ -----------------\)
- \(-11x^2+283=-3x^2-5 \\ \Leftrightarrow -11x^2+3x^2=-5-283 \\
\Leftrightarrow -8x^2 = -288 \\
\Leftrightarrow x^2 = \frac{-288}{-8}=36 \\
\Leftrightarrow x = 6 \vee x = -6 \\
V = \Big\{-6, 6 \Big\} \\ -----------------\)
- \(-x^2+0=0 \\
\Leftrightarrow -x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-1}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(2x^2-570=-5x^2-3 \\ \Leftrightarrow 2x^2+5x^2=-3+570 \\
\Leftrightarrow 7x^2 = 567 \\
\Leftrightarrow x^2 = \frac{567}{7}=81 \\
\Leftrightarrow x = 9 \vee x = -9 \\
V = \Big\{-9, 9 \Big\} \\ -----------------\)
- \(4x^2-9=6x^2+9 \\ \Leftrightarrow 4x^2-6x^2=9+9 \\
\Leftrightarrow -2x^2 = 18 \\
\Leftrightarrow x^2 = \frac{18}{-2} < 0 \\
V = \varnothing \\ -----------------\)
- \(4(-5x^2+4)=-(14x^2-232) \\ \Leftrightarrow -20x^2+16=-14x^2+232 \\
\Leftrightarrow -20x^2+14x^2=232-16 \\
\Leftrightarrow -6x^2 = 216 \\
\Leftrightarrow x^2 = \frac{216}{-6} < 0 \\
V = \varnothing \\ -----------------\)
- \(5x^2+245=0 \\
\Leftrightarrow 5x^2 = -245 \\
\Leftrightarrow x^2 = \frac{-245}{5} < 0 \\
V = \varnothing \\ -----------------\)
- \(-x^2-169=0 \\
\Leftrightarrow -x^2 = 169 \\
\Leftrightarrow x^2 = \frac{169}{-1} < 0 \\
V = \varnothing \\ -----------------\)
- \(-x^2+4=0 \\
\Leftrightarrow -x^2 = -4 \\
\Leftrightarrow x^2 = \frac{-4}{-1}=4 \\
\Leftrightarrow x = 2 \vee x = -2 \\
V = \Big\{-2, 2 \Big\} \\ -----------------\)
- \(7x^2-11=4x^2-8 \\ \Leftrightarrow 7x^2-4x^2=-8+11 \\
\Leftrightarrow 3x^2 = 3 \\
\Leftrightarrow x^2 = \frac{3}{3}=1 \\
\Leftrightarrow x = 1 \vee x = -1 \\
V = \Big\{-1, 1 \Big\} \\ -----------------\)
- \(7x^2+700=0 \\
\Leftrightarrow 7x^2 = -700 \\
\Leftrightarrow x^2 = \frac{-700}{7} < 0 \\
V = \varnothing \\ -----------------\)
- \(5(4x^2+4)=-(-13x^2-272) \\ \Leftrightarrow 20x^2+20=13x^2+272 \\
\Leftrightarrow 20x^2-13x^2=272-20 \\
\Leftrightarrow 7x^2 = 252 \\
\Leftrightarrow x^2 = \frac{252}{7}=36 \\
\Leftrightarrow x = 6 \vee x = -6 \\
V = \Big\{-6, 6 \Big\} \\ -----------------\)