Second Partial Derivative Test

In summary, the Second Partial Derivative Test is a method used in multivariable calculus to determine the nature of critical points of a function. It involves finding the second partial derivatives of a function and evaluating them at a critical point, with positive values indicating a local minimum, negative values indicating a local maximum, and zero values requiring further analysis. This test is more accurate than the First Partial Derivative Test as it takes into account the second derivative. The Second Partial Derivative Test can be extended to functions with any number of variables, but it can only be used for functions that are twice differentiable.
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I just need to know what is/how to computer [tex]\frac{\partial f}{\partial x \partial y}[/tex]
 
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Do you know how to find [tex]\frac{\partial y}{\partial x}[/itex]? To find the second derivative, just do it again: differentiate again whatever function you get from the first derivative.
 

FAQ: Second Partial Derivative Test

What is the Second Partial Derivative Test?

The Second Partial Derivative Test is a method used in multivariable calculus to determine the nature of critical points of a function, specifically whether they are maximum, minimum, or saddle points.

How is the Second Partial Derivative Test used?

The test involves finding the second partial derivatives of a function and evaluating them at a critical point. If the value of the second derivative is positive, the critical point is a local minimum. If the value is negative, the critical point is a local maximum. If the value is zero, further analysis is needed to determine the nature of the critical point.

What is the difference between the First and Second Partial Derivative Tests?

The First Partial Derivative Test only considers the first derivative of a function at a critical point, while the Second Partial Derivative Test takes into account the second derivative. This allows for a more accurate determination of the nature of the critical point.

Can the Second Partial Derivative Test be used for functions with more than two variables?

Yes, the Second Partial Derivative Test can be extended to functions with any number of variables. In this case, the second derivatives are represented by a Hessian matrix, and the test involves evaluating the eigenvalues of this matrix at the critical point.

Are there any limitations to the Second Partial Derivative Test?

The Second Partial Derivative Test can only be used for functions that are twice differentiable. If a function is not twice differentiable at a critical point, the test cannot be applied and other methods must be used to determine the nature of the critical point.

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