152k views
3 votes
Can you put f(x) = -4x^2 +8x-2 in vertex form

1 Answer

4 votes
Certainly! To write the quadratic function \(f(x) = -4x^2 + 8x - 2\) in vertex form, you'll want to complete the square. Here's the process:

1. Start with the given function:
\(f(x) = -4x^2 + 8x - 2\)

2. Factor out the leading coefficient (-4) from the first two terms:
\(f(x) = -4(x^2 - 2x) - 2\)

3. To complete the square inside the parentheses, take half of the coefficient of the \(x\) term (which is -2), square it, and add it inside the parentheses. Half of -2 is -1, and (-1)^2 is 1. So, add 1 inside the parentheses and subtract 4 (since you added 4 inside the parentheses, you need to subtract 4 outside to keep the expression equivalent):

\(f(x) = -4(x^2 - 2x + 1 - 1) - 2\)

4. Now, factor the perfect square trinomial inside the parentheses:
\(f(x) = -4((x - 1)^2 - 1) - 2\)

5. Distribute the -4 through the expression inside the parentheses:
\(f(x) = -4(x - 1)^2 + 4 - 2\)

6. Simplify the constants:
\(f(x) = -4(x - 1)^2 + 2\)

So, the vertex form of the quadratic function \(f(x) = -4x^2 + 8x - 2\) is \(f(x) = -4(x - 1)^2 + 2\), and the vertex of the parabola is at the point (1, 2).
User Haxhi
by
8.4k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories