A function y = 3u^3 + 4u - 10 and x = u + 8. How do I determine dy/dx

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The two functions y = 3u^3 + 4u - 10 and x= u+ 8 are both defined in terms of a common variable u.

To determine` dy/dx` , use the relation `dy/dx = (dy/(du))/(dx/(du))`

`dy/(du) = 9u^2 + 4` and `dx/(du) = 1`

`dy/dx = 9u^2 + 4`

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The two functions y = 3u^3 + 4u - 10 and x= u+ 8 are both defined in terms of a common variable u.

To determine` dy/dx` , use the relation `dy/dx = (dy/(du))/(dx/(du))`

`dy/(du) = 9u^2 + 4` and `dx/(du) = 1`

`dy/dx = 9u^2 + 4`

This could also be expressed in terms of x by using the function x = u + 8, `dy/dx = 9(x - 8)^2 + 4 = 9x^2 - 144x + 580`

The derivative `dy/dx = 9u^2 + 4`

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