Whakaoti i te 81c^2-16=0

$$81 c ^ { 2 } - 16 = 0$$

Whakaoti mō c

$$c=\frac{4}{9}\approx 0.444444444$$

$$c=-\frac{4}{9}\approx -0.444444444$$

Ngā Hipanga Whakamahi Rerekētanga o ngā Pūrua

Whakaarohia te 81c^{2}-16. Tuhia anō te 81c^{2}-16 hei \left(9c\right)^{2}-4^{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).

$$\left(9c-4\right)\left(9c+4\right)=0$$

Hei kimi otinga whārite, me whakaoti te 9c-4=0 me te 9c+4=0.

$$c=\frac{4}{9} c=-\frac{4}{9}$$

Ngā Upane mā te Kimi Pūtakerua

Me tāpiri te 16 ki ngā taha e rua. Ko te tau i tāpiria he kore ka hua koia tonu.

$$81c^{2}=16$$

Whakawehea ngā taha e rua ki te 81.

$$c^{2}=\frac{16}{81}$$

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

$$c=\frac{4}{9} c=-\frac{4}{9}$$

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.

$$81c^{2}-16=0$$

Kei te āhua arowhānui tēnei whārite: ax^{2}+bx+c=0. Me whakakapi 81 mō a, 0 mō b, me -16 mō c i te tikanga tātai pūrua, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$c=\frac{0±\sqrt{0^{2}-4\times 81\left(-16\right)}}{2\times 81}$$

Pūrua 0.

$$c=\frac{0±\sqrt{-4\times 81\left(-16\right)}}{2\times 81}$$

Whakareatia -4 ki te 81.

$$c=\frac{0±\sqrt{-324\left(-16\right)}}{2\times 81}$$

Whakareatia -324 ki te -16.

$$c=\frac{0±\sqrt{5184}}{2\times 81}$$

Tuhia te pūtakerua o te 5184.

$$c=\frac{0±72}{2\times 81}$$

Whakareatia 2 ki te 81.

$$c=\frac{0±72}{162}$$

Nā, me whakaoti te whārite c=\frac{0±72}{162} ina he tāpiri te ±. Whakahekea te hautanga \frac{72}{162} ki ōna wāhi pāpaku rawa mā te tango me te whakakore i te 18.

$$c=\frac{4}{9}$$

Nā, me whakaoti te whārite c=\frac{0±72}{162} ina he tango te ±. Whakahekea te hautanga \frac{-72}{162} ki ōna wāhi pāpaku rawa mā te tango me te whakakore i te 18.

$$c=-\frac{4}{9}$$

Kua oti te whārite te whakatau.

$$c=\frac{4}{9} c=-\frac{4}{9}$$