Derivative Functions
The derivative function gives the derivative of a function at each point in the domain of the original function for which the derivative is defined. We can formally define a derivative function as follows.
Definition:
let f be a function. The derivative function, denoted by f', is the function whose domain consists of those values of x such that the following limit exists:

3y+4+3y-y=-6
6y-y+4=-6
5y+4=-6
5y=-10
y=-2
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Answer:
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