How do you find the axis of symmetry, and the maximum or minimum value of the function f(x)=3x2+7x4?

1 Answer
Sep 22, 2017

See the explanation: A sort of cheat approach.

Explanation:

Firstly the coefficient of x2 is negative so the graph is of form . Thus we have a maximum.

Write the equation as: y=3(x273x)4

Thus xmaximum is at x=(12)×(73)=+76

Now it is just a matter of substitution to determine ymaximum

Tony B