Whakaoti i te 2x^2-8=0

$$2 { x }^{ 2 } -8 = 0$$

Whakaoti mō x

$$x=2$$

$$x=-2$$

Ngā Hipanga Whakamahi Rerekētanga o ngā Pūrua

Whakawehea ngā taha e rua ki te 2.

$$x^{2}-4=0$$

Whakaarohia te x^{2}-4. Tuhia anō te x^{2}-4 hei x^{2}-2^{2}. Ka taea te rerekētanga o ngā pūrua te whakatauwehe mā te ture: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).

$$\left(x-2\right)\left(x+2\right)=0$$

Hei kimi otinga whārite, me whakaoti te x-2=0 me te x+2=0.

$$x=2 x=-2$$

Ngā Upane mā te Kimi Pūtakerua

Me tāpiri te 8 ki ngā taha e rua. Ko te tau i tāpiria he kore ka hua koia tonu.

$$2x^{2}=8$$

Whakawehea ngā taha e rua ki te 2.

$$x^{2}=\frac{8}{2}$$

Whakawehea te 8 ki te 2, kia riro ko 4.

$$x^{2}=4$$

Tuhia te pūtakerua o ngā taha e rua o te whārite.

$$x=2 x=-2$$

Ngā Upane e Whakamahi ana i te Tikanga Tātai Pūrua

Ko ngā tikanga tātai pūrua pēnei i tēnei nā, me te kīanga tau x^{2} engari kāore he kīanga tau x, ka taea tonu te whakaoti mā te whakamahi i te tikanga tātai pūrua, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, ina tuhia ki te tānga ngahuru: ax^{2}+bx+c=0.

$$2x^{2}-8=0$$

Kei te āhua arowhānui tēnei whārite: ax^{2}+bx+c=0. Me whakakapi 2 mō a, 0 mō b, me -8 mō c i te tikanga tātai pūrua, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{0±\sqrt{0^{2}-4\times 2\left(-8\right)}}{2\times 2}$$

Pūrua 0.

$$x=\frac{0±\sqrt{-4\times 2\left(-8\right)}}{2\times 2}$$

Whakareatia -4 ki te 2.

$$x=\frac{0±\sqrt{-8\left(-8\right)}}{2\times 2}$$

Whakareatia -8 ki te -8.

$$x=\frac{0±\sqrt{64}}{2\times 2}$$

Tuhia te pūtakerua o te 64.

$$x=\frac{0±8}{2\times 2}$$

Whakareatia 2 ki te 2.

$$x=\frac{0±8}{4}$$

Nā, me whakaoti te whārite x=\frac{0±8}{4} ina he tāpiri te ±. Whakawehe 8 ki te 4.

$$x=2$$

Nā, me whakaoti te whārite x=\frac{0±8}{4} ina he tango te ±. Whakawehe -8 ki te 4.

$$x=-2$$

Kua oti te whārite te whakatau.

$$x=2 x=-2$$