Los de vierkantsvergelijking op zonder de discriminant te gebruiken
- \(4(6x^2-10)=-(-16x^2-1760)\)
- \(2x^2+32=0\)
- \(5x^2-45=0\)
- \(-3x^2+0=0\)
- \(-3x^2+27=0\)
- \(3x^2-6=2x^2-6\)
- \(9x^2+893=5x^2-7\)
- \(-3x^2-18=3x^2+6\)
- \(-8x^2+283=-6x^2-5\)
- \(-5x^2-1363=2x^2+9\)
- \(-4x^2-11=-3x^2-2\)
- \(3(4x^2-3)=-(-17x^2-971)\)
Los de vierkantsvergelijking op zonder de discriminant te gebruiken
Verbetersleutel
- \(4(6x^2-10)=-(-16x^2-1760) \\ \Leftrightarrow 24x^2-40=16x^2+1760 \\
\Leftrightarrow 24x^2-16x^2=1760+40 \\
\Leftrightarrow 8x^2 = 1800 \\
\Leftrightarrow x^2 = \frac{1800}{8}=225 \\
\Leftrightarrow x = 15 \vee x = -15 \\
V = \Big\{-15, 15 \Big\} \\ -----------------\)
- \(2x^2+32=0 \\
\Leftrightarrow 2x^2 = -32 \\
\Leftrightarrow x^2 = \frac{-32}{2} < 0 \\
V = \varnothing \\ -----------------\)
- \(5x^2-45=0 \\
\Leftrightarrow 5x^2 = 45 \\
\Leftrightarrow x^2 = \frac{45}{5}=9 \\
\Leftrightarrow x = 3 \vee x = -3 \\
V = \Big\{-3, 3 \Big\} \\ -----------------\)
- \(-3x^2+0=0 \\
\Leftrightarrow -3x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{-3}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(-3x^2+27=0 \\
\Leftrightarrow -3x^2 = -27 \\
\Leftrightarrow x^2 = \frac{-27}{-3}=9 \\
\Leftrightarrow x = 3 \vee x = -3 \\
V = \Big\{-3, 3 \Big\} \\ -----------------\)
- \(3x^2-6=2x^2-6 \\ \Leftrightarrow 3x^2-2x^2=-6+6 \\
\Leftrightarrow x^2 = 0 \\
\Leftrightarrow x^2 = \frac{0}{1}\\
\Leftrightarrow x = 0 \\
V = \Big\{ 0 \Big\} \\ -----------------\)
- \(9x^2+893=5x^2-7 \\ \Leftrightarrow 9x^2-5x^2=-7-893 \\
\Leftrightarrow 4x^2 = -900 \\
\Leftrightarrow x^2 = \frac{-900}{4} < 0 \\
V = \varnothing \\ -----------------\)
- \(-3x^2-18=3x^2+6 \\ \Leftrightarrow -3x^2-3x^2=6+18 \\
\Leftrightarrow -6x^2 = 24 \\
\Leftrightarrow x^2 = \frac{24}{-6} < 0 \\
V = \varnothing \\ -----------------\)
- \(-8x^2+283=-6x^2-5 \\ \Leftrightarrow -8x^2+6x^2=-5-283 \\
\Leftrightarrow -2x^2 = -288 \\
\Leftrightarrow x^2 = \frac{-288}{-2}=144 \\
\Leftrightarrow x = 12 \vee x = -12 \\
V = \Big\{-12, 12 \Big\} \\ -----------------\)
- \(-5x^2-1363=2x^2+9 \\ \Leftrightarrow -5x^2-2x^2=9+1363 \\
\Leftrightarrow -7x^2 = 1372 \\
\Leftrightarrow x^2 = \frac{1372}{-7} < 0 \\
V = \varnothing \\ -----------------\)
- \(-4x^2-11=-3x^2-2 \\ \Leftrightarrow -4x^2+3x^2=-2+11 \\
\Leftrightarrow -x^2 = 9 \\
\Leftrightarrow x^2 = \frac{9}{-1} < 0 \\
V = \varnothing \\ -----------------\)
- \(3(4x^2-3)=-(-17x^2-971) \\ \Leftrightarrow 12x^2-9=17x^2+971 \\
\Leftrightarrow 12x^2-17x^2=971+9 \\
\Leftrightarrow -5x^2 = 980 \\
\Leftrightarrow x^2 = \frac{980}{-5} < 0 \\
V = \varnothing \\ -----------------\)