y is a composite function in the form `y=f(g(x))` with `f(X)=tan(X)` and `g(x)=ln(ax+b)` .
The derivative is
Remark. There is a second expression for the derivative of tan X:
It is the same function but written with a different expression. Using this expression in the derivative of the composite fonction we find a different expression of the same derivative:
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