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Consider the function z=g(x,y)=X³ +13 3 (a) Compute the partial

derivatives of g. gx(x,y) = x² 2-y gy(x,y)=2 - X (b) Find all
critical points of g(x,y). List them in order from smallest x to
largest
8. [4/7 Points] DETAILS PREVIOUS ANSWERS Consider the function z=g(x,y)=X+X-XY+7. (a) Compute the partial derivatives of g. gx(x,y)=x²-y gy(x,y)=2_ -x (b) Find all critical points of g(x,y). List the

User Sebf
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2 Answers

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Final answer:

The partial derivatives of the function z = g(x,y) are gx(x,y) = 2x - y and gy(x,y) = -x. The function has a single critical point at (0, 0), found by setting the partial derivatives equal to zero and solving for x and y.

Step-by-step explanation:

To address the student's question regarding partial derivatives and critical points, we must evaluate the partial derivatives of the function z = g(x,y) = x + x - xy + 7. There seems to be some confusion in the presentation of the function. Assuming the function z = g(x,y) = x^2 - xy + 7, the partial derivatives are calculated as follows:

  • For gx(x,y), which is the partial derivative with respect to x, we get gx(x,y) = 2x - y.
  • For gy(x,y), which is the partial derivative with respect to y, we get gy(x,y) = -x.

To find the critical points, we set these partial derivatives equal to zero:

  • 2x - y = 0
  • -x = 0

Solving these equations, we find that the only critical point is located at (x, y) = (0, 0).

There are no other critical points, and the enumeration by the x-values does not apply as there's only one critical point.

User David Motilla
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Final Answer:

The partial derivatives of the function
\(g(x, y) = x^3 + (13)/(3)\) are
\(g_x(x, y) = 3x^2\) and \(g_y(x, y) = 0\). The critical point, where both partial derivatives are zero, is (0, 2).

Step-by-step explanation:

Certainly, let's go through the detailed calculations step by step.

Given Information:


\[ g(x, y) = x^3 + (13)/(3) \]

Partial Derivatives:

(a) To find the partial derivatives, differentiate
\(g\) with respect to
\(x\) and \(y\):


\[ g_x(x, y) = (\partial g)/(\partial x) = 3x^2 \]


\[ g_y(x, y) = (\partial g)/(\partial y) = 0 \]

(b) To find the critical points, set
\(g_x\) and \(g_y\) equal to zero and solve for
\(x\) and \(y\):


\[ 3x^2 = 0 \implies x = 0 \]


\[ 2 - x = 0 \implies x = 2 \]

Critical Point:

The critical point is where both partial derivatives are zero. Combining the solutions, we get
\( (x, y) = (0, 2) \).

(a) The partial derivatives
\(g_x\) and \(g_y\) are obtained by differentiating
\(g(x, y)\) with respect to
\(x\) and \(y\), respectively. The derivative of
\(x^3\) with respect to
\(x\) is \(3x^2\) , and the constant term
\((13)/(3)\) differentiates to zero. Therefore,
\(g_x(x, y) = 3x^2\) and \(g_y(x, y) = 0\).

(b) To find the critical points, we set
\(g_x\) and \(g_y\) equal to zero. For
\(g_x\), \(3x^2 = 0\) implies
\(x = 0\). For \(g_y\), \(2 - x = 0\) results in
\(x = 2\). Combining these solutions, the critical point is
\( (0, 2) \), where both partial derivatives are zero.

In summary, the partial derivatives
\(g_x(x, y) = 3x^2\) and \(g_y(x, y) = 0\). The critical point is
\( (0, 2) \), and these calculations provide a detailed understanding of the function's behavior and critical characteristics.