Differentiate the function with respect to $x$: $\frac{\sin (a x+b)}{\cos (c x+d)}$

Let $f(x) = \frac{\sin (a x+b)}{\cos (c x+d)}$.
Using the quotient rule $\frac{d}{dx} \left[ \frac{g(x)}{h(x)} \right] = \frac{g'(x)h(x) - g(x)h'(x)}{[h(x)]^2}$,where $g(x) = \sin(ax+b)$ and $h(x) = \cos(cx+d)$.
First,find the derivatives using the chain rule:
$g'(x) = \frac{d}{dx} [\sin(ax+b)] = \cos(ax+b) \cdot \frac{d}{dx}(ax+b) = a \cos(ax+b)$.
$h'(x) = \frac{d}{dx} [\cos(cx+d)] = -\sin(cx+d) \cdot \frac{d}{dx}(cx+d) = -c \sin(cx+d)$.
Now,substitute these into the quotient rule formula:
$f'(x) = \frac{[a \cos(ax+b)] \cdot [\cos(cx+d)] - [\sin(ax+b)] \cdot [-c \sin(cx+d)]}{[\cos(cx+d)]^2}$.
$f'(x) = \frac{a \cos(ax+b) \cos(cx+d) + c \sin(ax+b) \sin(cx+d)}{\cos^2(cx+d)}$.
This can be simplified as:
$f'(x) = \frac{a \cos(ax+b) \cos(cx+d)}{\cos^2(cx+d)} + \frac{c \sin(ax+b) \sin(cx+d)}{\cos^2(cx+d)}$.
$f'(x) = a \cos(ax+b) \sec(cx+d) + c \sin(ax+b) \tan(cx+d) \sec(cx+d)$.