Find Decreasing Intervals for the Quadratic Function: y = 3x² - 6x + 4

Find the intervals where the function is decreasing:

y=3x26x+4 y=3x^2-6x+4

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:00 Find the domain of decrease of the function
00:03 We'll use the formula to find the X value at the vertex
00:08 Identify the trinomial coefficients
00:12 We'll substitute appropriate values according to the given data and solve for X
00:22 This is the X value at the vertex point
00:25 The coefficient A is positive, therefore the parabola has a minimum point
00:30 According to the graph, we'll deduce the domain of decrease of the function
00:35 And this is the solution to the question

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

Find the intervals where the function is decreasing:

y=3x26x+4 y=3x^2-6x+4

2

Step-by-step solution

To find where the function y=3x26x+4 y = 3x^2 - 6x + 4 is decreasing, we first need to find its derivative. This involves the following steps:

  • Step 1: Compute the derivative of the function.

The derivative of the function, using the formula for the derivative of a quadratic function ax2+bx+c ax^2 + bx + c , is given by:

y=ddx(3x26x+4)=6x6 y' = \frac{d}{dx}(3x^2 - 6x + 4) = 6x - 6

  • Step 2: Set the derivative less than zero to find the decreasing interval.

We set the derivative 6x6 6x - 6 less than zero:

6x6<0 6x - 6 < 0

Simplifying the inequality, we get:

6x<6 6x < 6

x<1 x < 1

  • Step 3: Identify the interval for decreasing behavior.

The inequality x<1 x < 1 indicates the interval where the function is decreasing. Note that this function represents a parabola that opens upwards, and hence, it decreases as x x approaches the vertex from the left and increases as x x moves right after the vertex.

Therefore, the interval where the function y=3x26x+4 y = 3x^2 - 6x + 4 is decreasing is x<1 x < 1 .

3

Final Answer

x<1 x<1

Practice Quiz

Test your knowledge with interactive questions

Note that the graph of the function shown below does not intersect the x-axis

The parabola's vertex is A

Identify the interval where the function is decreasing:

XXXAAA

🌟 Unlock Your Math Potential

Get unlimited access to all 18 The Quadratic Function questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations