Whakaoti mō x
x=\sqrt{5}+2\approx 4.236067977
x=2-\sqrt{5}\approx -0.236067977
Graph
Tohaina
Kua tāruatia ki te papatopenga
x^{2}-4x-1=0
Whakareatia ngā taha e rua o te whārite ki te \left(x^{2}+1\right)^{2}.
x=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\left(-1\right)}}{2}
Kei te āhua arowhānui tēnei whārite: ax^{2}+bx+c=0. Me whakakapi 1 mō a, -4 mō b, me -1 mō c i te tikanga tātai pūrua, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-4\right)±\sqrt{16-4\left(-1\right)}}{2}
Pūrua -4.
x=\frac{-\left(-4\right)±\sqrt{16+4}}{2}
Whakareatia -4 ki te -1.
x=\frac{-\left(-4\right)±\sqrt{20}}{2}
Tāpiri 16 ki te 4.
x=\frac{-\left(-4\right)±2\sqrt{5}}{2}
Tuhia te pūtakerua o te 20.
x=\frac{4±2\sqrt{5}}{2}
Ko te tauaro o -4 ko 4.
x=\frac{2\sqrt{5}+4}{2}
Nā, me whakaoti te whārite x=\frac{4±2\sqrt{5}}{2} ina he tāpiri te ±. Tāpiri 4 ki te 2\sqrt{5}.
x=\sqrt{5}+2
Whakawehe 4+2\sqrt{5} ki te 2.
x=\frac{4-2\sqrt{5}}{2}
Nā, me whakaoti te whārite x=\frac{4±2\sqrt{5}}{2} ina he tango te ±. Tango 2\sqrt{5} mai i 4.
x=2-\sqrt{5}
Whakawehe 4-2\sqrt{5} ki te 2.
x=\sqrt{5}+2 x=2-\sqrt{5}
Kua oti te whārite te whakatau.
x^{2}-4x-1=0
Whakareatia ngā taha e rua o te whārite ki te \left(x^{2}+1\right)^{2}.
x^{2}-4x=1
Me tāpiri te 1 ki ngā taha e rua. Ko te tau i tāpiria he kore ka hua koia tonu.
x^{2}-4x+\left(-2\right)^{2}=1+\left(-2\right)^{2}
Whakawehea te -4, te tau whakarea o te kīanga tau x, ki te 2 kia riro ai te -2. Nā, tāpiria te pūrua o te -2 ki ngā taha e rua o te whārite. Mā konei e pūrua tika tonu ai te taha mauī o te whārite.
x^{2}-4x+4=1+4
Pūrua -2.
x^{2}-4x+4=5
Tāpiri 1 ki te 4.
\left(x-2\right)^{2}=5
Tauwehea x^{2}-4x+4. Ko te tikanga pūnoa, ina ko x^{2}+bx+c he pūrua tika pūrua tika pū, ka taea taua mea te tauwehea i ngā wā katoa hei \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-2\right)^{2}}=\sqrt{5}
Tuhia te pūtakerua o ngā taha e rua o te whārite.
x-2=\sqrt{5} x-2=-\sqrt{5}
Whakarūnātia.
x=\sqrt{5}+2 x=2-\sqrt{5}
Me tāpiri 2 ki ngā taha e rua o te whārite.
Ngā Tauira
whārite tapawhā
{ x } ^ { 2 } - 4 x - 5 = 0
Āhuahanga
4 \sin \theta \cos \theta = 2 \sin \theta
whārite paerangi
y = 3x + 4
Arithmetic
699 * 533
Poukapa
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
whārite Simultaneous
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Whakarerekētanga
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Whakaurunga
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Ngā Tepe
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}