Why is the derivative of y = f (x) = x equal to 1 and the derivative of y = f (x) = C equal to 0 Ask the teacher to explain to me clearly, I almost fainted

The derivative of y = f (x) = x is the derivative of X, that is, X '= 1
And y = f (x) = C is a constant function, the derivative of any constant function is zero!

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