Whakaoti i te left(-2a+2right)^2-4left(a^2-a-2right)>0

$${ \left(-2a+2 \right) }^{ 2 } -4 \left( { a }^{ 2 } -a-2 \right) > 0$$

Whakaoti mō a

$$a<3$$

Ngā Upane Otinga

Whakamahia te ture huarua \left(a+b\right)^{2}=a^{2}+2ab+b^{2} hei whakaroha \left(-2a+2\right)^{2}.

$$4a^{2}-8a+4-4\left(a^{2}-a-2\right)>0$$

Whakamahia te āhuatanga tohatoha hei whakarea te -4 ki te a^{2}-a-2.

$$4a^{2}-8a+4-4a^{2}+4a+8>0$$

Pahekotia te 4a^{2} me -4a^{2}, ka 0.

$$-8a+4+4a+8>0$$

Pahekotia te -8a me 4a, ka -4a.

$$-4a+4+8>0$$

Tāpirihia te 4 ki te 8, ka 12.

$$-4a+12>0$$

Tangohia te 12 mai i ngā taha e rua. Ko te tau i tango i te kore ka hua ko tōna korenga.

$$-4a>-12$$

Whakawehea ngā taha e rua ki te -4. I te mea he tōraro a -4, ka huri te ahunga koreōrite.

$$a<\frac{-12}{-4}$$

Whakawehea te -12 ki te -4, kia riro ko 3.

$$a<3$$