Question

Find the vertex of the following function.
f(x) = -2x2 - 4x
Enter your answer as an ordered pair, example: (1, -2)

Answer 1

\[y=-2x^{2}-4x\]
We need to derive:
\[y^{'}=-4x-4\]
Set the derivative equal to 0:
\[-4x-4=0\]
Solve for x:
\[-4x=4\]
\[x=-1\]
Plug into original problem to find y:
\[y=-2(-1)^{2}-4(-1)\]
\[y=-2+4\]
\[y=2\]
So the ordered pair is:
(-1,2)

Answer 2

ty u actully showed how to solve it

Answer 3

You're welcome. Always best to learn how to solve the problems. The test won't have someone looking over your shoulder to help, so happy to explain :)