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Find the first partial derivatives of the following functions. $$g(x, y, z)=2 x^{2} y-3 x z^{4}+10 y^{2} z^{2}$$

Short Answer

Expert verified
Question: Find the first partial derivatives of the function $$g(x, y, z) = 2 x^{2} y - 3 x z^{4} + 10 y^{2} z^{2}$$ with respect to x, y, and z. Answer: The first partial derivatives of the function g(x, y, z) are: $$\frac{\partial g}{\partial x} = 4xy - 3z^4,$$ $$\frac{\partial g}{\partial y} = 2x^2 + 20yz^2,$$ $$\frac{\partial g}{\partial z} = -12xz^3 + 20y^2z$$.

Step by step solution

01

Calculate ∂g/∂x

To find the partial derivative of the function g(x, y, z) with respect to x, we treat y and z as constants and differentiate g with respect to x: $$\frac{\partial g}{\partial x} = \frac{\partial}{\partial x}(2 x^{2} y - 3 x z^{4} + 10 y^{2} z^{2})$$ The derivative of each term is as follows: - The derivative of \(2x^2y\) with respect to x is \(4xy\) - The derivative of \(-3xz^4\) with respect to x is \(-3z^4\) - Since it does not contain x, the term \(10y^2z^2\) has no contribution. Therefore, $$\frac{\partial g}{\partial x} = 4xy - 3z^4$$.
02

Calculate ∂g/∂y

To find the partial derivative of the function g(x, y, z) with respect to y, we treat x and z as constants and differentiate g with respect to y: $$\frac{\partial g}{\partial y} = \frac{\partial}{\partial y}(2 x^{2} y - 3 x z^{4} + 10 y^{2} z^{2})$$ The derivative of each term is as follows: - The derivative of \(2x^2y\) with respect to y is \(2x^2\) - Since it does not contain y, the term \(-3xz^4\) has no contribution. - The derivative of \(10y^2z^2\) with respect to y is \(20yz^2\) Therefore, $$\frac{\partial g}{\partial y} = 2x^2 + 20yz^2$$.
03

Calculate ∂g/∂z

To find the partial derivative of the function g(x, y, z) with respect to z, we treat x and y as constants and differentiate g with respect to z: $$\frac{\partial g}{\partial z} = \frac{\partial}{\partial z}(2 x^{2} y - 3 x z^{4} + 10 y^{2} z^{2})$$ The derivative of each term is as follows: - Since it does not contain z, the term \(2x^2y\) has no contribution. - The derivative of \(-3xz^4\) with respect to z is \(-12xz^3\) - The derivative of \(10y^2z^2\) with respect to z is \(20y^2z\) Therefore, $$\frac{\partial g}{\partial z} = -12xz^3 + 20y^2z$$. Finally, the first partial derivatives of the function g(x, y, z) are: $$\frac{\partial g}{\partial x} = 4xy - 3z^4,$$ $$\frac{\partial g}{\partial y} = 2x^2 + 20yz^2,$$ $$\frac{\partial g}{\partial z} = -12xz^3 + 20y^2z$$.

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