To effectively sketch the graph of the function y=x3−x, it is essential to identify key points, observe symmetry, and analyze the behavior of the graph as x approaches large values.
1. Finding the Roots: To locate the roots, we set y=0. Solving the equation x3−x=0 yields:
x(x2−1)=0From this, we find the roots x=0, x=1, and x=−1. These points represent where the graph intersects the x-axis.
2. Determining Turning Points: Next, we need to find the turning points by calculating the first derivative of the function:
y′=3x2−1Setting the first derivative to zero, we solve:
3x2−1=0This gives us the solutions:
x=±31To classify these turning points, we calculate the second derivative:
y′′=6xEvaluating the second derivative at the turning points:
This indicates a local minimum.
This indicates a local maximum.
3. Evaluating the Function at Turning Points: Now, we compute the values of y at these turning points:
4. Analyzing Symmetry: The graph exhibits symmetry about the origin, which can be confirmed by the property y(−x)=−y(x). This indicates that the function is odd.
5. Examining End Behavior: Finally, we analyze the end behavior of the function. As x approaches infinity (x→∞), y also approaches infinity (y→∞). Conversely, as x approaches negative infinity (x→−∞), y approaches negative infinity (y→−∞). This means the graph extends infinitely in both directions.
6. Sketching the Graph: With the roots, turning points, and symmetry established, you can proceed to plot these key points. Ensure the curve passes through the roots at (0,0), (1,0), and (−1,0) and follows the identified behavior, including the local maximum at (−31,−332) and the local minimum at (31,332). The final sketch will be a smooth curve that reflects all the analyzed characteristics.
![]() 100% | ![]() Global | ![]() 97% | |
---|---|---|---|
Professional Tutors | International Tuition | Independent School Entrance Success | |
All of our elite tutors are full-time professionals, with at least five years of tuition experience and over 5000 accrued teaching hours in their subject. | Based in Cambridge, with operations spanning the globe, we can provide our services to support your family anywhere. | Our families consistently gain offers from at least one of their target schools, including Eton, Harrow, Wellington and Wycombe Abbey. |
![]() 100% |
---|
Professional Tutors |
All of our elite tutors are full-time professionals, with at least five years of tuition experience and over 5000 accrued teaching hours in their subject. |
![]() Global |
International Tuition |
Based in Cambridge, with operations spanning the globe, we can provide our services to support your family anywhere. |
![]() 97% |
Independent School Entrance Success |
Our families consistently gain offers from at least one of their target schools, including Eton, Harrow, Wellington and Wycombe Abbey. |
At the Beyond Tutors we recognise that no two students are the same.
That’s why we’ve transcended the traditional online tutoring model of cookie-cutter solutions to intricate educational problems. Instead, we devise a bespoke tutoring plan for each individual student, to support you on your path to academic success.
To help us understand your unique educational needs, we provide a free 30-minute consultation with one of our founding partners, so we can devise the tutoring plan that’s right for you.
To ensure we can best prepare for this consultation, we ask you to fill out the short form below.