Whakaoti i te {l}{f(x)=-x^2+3x+5}{x=-3/5}

$$\left. \begin{array} { l } { f ( x ) = - x ^ { 2 } + 3 x + 5 } \\ { x = - \frac { 3 } { 5 } } \end{array} \right.$$

Whakaoti mō f, x

$$x=-\frac{3}{5}=-0.6$$

$$f = -\frac{71}{15} = -4\frac{11}{15} \approx -4.733333333$$

Ngā Upane Otinga

Whakaarohia te whārite tuatahi. Me kōkuhu ngā uara tāupe mōhiotia ki te whārite.

$$f\left(-\frac{3}{5}\right)=-\left(-\frac{3}{5}\right)^{2}+3\left(-\frac{3}{5}\right)+5$$

Tātaihia te -\frac{3}{5} mā te pū o 2, kia riro ko \frac{9}{25}.

$$f\left(-\frac{3}{5}\right)=-\frac{9}{25}+3\left(-\frac{3}{5}\right)+5$$

Whakareatia te 3 ki te -\frac{3}{5}, ka -\frac{9}{5}.

$$f\left(-\frac{3}{5}\right)=-\frac{9}{25}-\frac{9}{5}+5$$

Tangohia te \frac{9}{5} i te -\frac{9}{25}, ka -\frac{54}{25}.

$$f\left(-\frac{3}{5}\right)=-\frac{54}{25}+5$$

Tāpirihia te -\frac{54}{25} ki te 5, ka \frac{71}{25}.

$$f\left(-\frac{3}{5}\right)=\frac{71}{25}$$

Me whakarea ngā taha e rua ki te -\frac{5}{3}, te tau utu o -\frac{3}{5}.

$$f=\frac{71}{25}\left(-\frac{5}{3}\right)$$

Whakareatia te \frac{71}{25} ki te -\frac{5}{3}, ka -\frac{71}{15}.

$$f=-\frac{71}{15}$$

Kua oti te pūnaha te whakatau.

$$f=-\frac{71}{15} x=-\frac{3}{5}$$