Whakaoti i te 2x^2+7=8

$$2 x ^ { 2 } + 7 = 8$$

Whakaoti mō x

$$x=\frac{\sqrt{2}}{2}\approx 0.707106781$$

$$x=-\frac{\sqrt{2}}{2}\approx -0.707106781$$

Ngā Upane mā te Kimi Pūtakerua

Tangohia te 7 mai i ngā taha e rua.

$$2x^{2}=8-7$$

Tangohia te 7 i te 8, ka 1.

$$2x^{2}=1$$

Whakawehea ngā taha e rua ki te 2.

$$x^{2}=\frac{1}{2}$$

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

$$x=\frac{\sqrt{2}}{2} x=-\frac{\sqrt{2}}{2}$$

Ngā Upane e Whakamahi ana i te Tikanga Tātai Pūrua

Tangohia te 8 mai i ngā taha e rua.

$$2x^{2}+7-8=0$$

Tangohia te 8 i te 7, ka -1.

$$2x^{2}-1=0$$

Kei te āhua arowhānui tēnei whārite: ax^{2}+bx+c=0. Me whakakapi 2 mō a, 0 mō b, me -1 mō c i te tikanga tātai pūrua, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{0±\sqrt{0^{2}-4\times 2\left(-1\right)}}{2\times 2}$$

Pūrua 0.

$$x=\frac{0±\sqrt{-4\times 2\left(-1\right)}}{2\times 2}$$

Whakareatia -4 ki te 2.

$$x=\frac{0±\sqrt{-8\left(-1\right)}}{2\times 2}$$

Whakareatia -8 ki te -1.

$$x=\frac{0±\sqrt{8}}{2\times 2}$$

Tuhia te pūtakerua o te 8.

$$x=\frac{0±2\sqrt{2}}{2\times 2}$$

Whakareatia 2 ki te 2.

$$x=\frac{0±2\sqrt{2}}{4}$$

Nā, me whakaoti te whārite x=\frac{0±2\sqrt{2}}{4} ina he tāpiri te ±.

$$x=\frac{\sqrt{2}}{2}$$

Nā, me whakaoti te whārite x=\frac{0±2\sqrt{2}}{4} ina he tango te ±.

$$x=-\frac{\sqrt{2}}{2}$$

Kua oti te whārite te whakatau.

$$x=\frac{\sqrt{2}}{2} x=-\frac{\sqrt{2}}{2}$$