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Use the Chain Rule to find dz/dt. z = sin(x) cos(y), x = √t, y = 4/t

User Btleffler
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Final answer:

To find dz/dt using the Chain Rule, we need to find the partial derivatives of z with respect to x and y, and then find dx/dt and dy/dt. Finally, we can apply the Chain Rule to find dz/dt.

Step-by-step explanation:

To find dz/dt using the Chain Rule, we can start by finding the partial derivatives of z with respect to x and y. Then we can use the given expressions for x and y to find dx/dt and dy/dt. Finally, we can apply the Chain Rule to find dz/dt.

First, let's find the partial derivatives of z:

∂z/∂x = cos(x)cos(y)

∂z/∂y = -sin(x)sin(y)

Next, let's find dx/dt and dy/dt:

dx/dt = (1/2√t)

dy/dt = -4/t^2

Finally, we can apply the Chain Rule:

dz/dt = (∂z/∂x) * (dx/dt) + (∂z/∂y) * (dy/dt)

Substituting the partial derivatives and the expressions for dx/dt and dy/dt:

dz/dt = (cos(x)cos(y)) * (1/2√t) + (-sin(x)sin(y)) * (-4/t^2)

Simplifying further:

dz/dt = (cos(√t)cos(4/t)) * (1/2√t) + (-sin(√t)sin(4/t)) * (-4/t^2)

So, dz/dt = (cos(√t)cos(4/t)) * (1/2√t) + (sin(√t)sin(4/t)) * (4/t^2)

User Zing Lee
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