Well, looking at the graph, notice, its vertex is at 0,9, and it passes through the points -3,0 and 3,0, so hmm let's use 3,0, to get the equation of f(x)

$\bf ~~~~~~\textit{parabola vertex form}
\\\\
\begin{array}{llll}
\boxed{y=a(x- h)^2+ k}\\\\
x=a(y- k)^2+ h
\end{array}
\qquad\qquad
vertex~~(\stackrel{}{ h},\stackrel{}{ k})\\\\
-------------------------------$

$\bf vertex~(0,9)~
\begin{cases}
h=0\\
k=9
\end{cases}\implies y=a(x-0)^2+9
\\\\\\
\textit{we also know that }
\begin{cases}
x=3\\
y=0
\end{cases}\implies 0=a(3-0)^2+9
\\\\\\
-9=9a\implies \cfrac{-9}{9}=a\implies -1=a\quad thus\quad \boxed{y=-x^2+9}
\\\\\\
\left. \cfrac{dy}{dx}=-2x \right|_{x=3}\implies -6$

3 0

3 years ago

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What is the simplest form of 5/6 divided by 1/2

nekit [7.7K]

Answer:

$\frac{ \frac{ \frac{5}{6} }{1} }{2} = \frac{5}{3} = 1 \times \frac{2}{3}$

4 0

2 years ago

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Top top term of a fraction ​

Top top term of a fraction