Question

select form to find quadratic feature
score: 0/3 penalty: none
question
a quadratic function f(x) is hidden from view. you must find all intervals where f(x) is decreasing. choose the form of the quadratic function f(x) that you would like to see in order to answer the question most efficiently.
form: vertex form
f(x) = -2(x - 1)^2 + 8
answer attempt 2 out of 2

Explanation:

Step1: Identify vertex and parabola direction

Vertex form: $f(x)=a(x-h)^2+k$. Here, $a=-2$, $(h,k)=(1,8)$. Since $a<0$, parabola opens downward.

Step2: Determine decreasing interval

For downward opening parabola, function decreases to the right of vertex $x=1$.
The interval is $x>1$, or $(1, \infty)$.

Answer:

$(1, \infty)$