# Find the derivative of the following functions ( it is to be understood that a, b, c, d, p, q, r and s are fixed non-zero constants and m and n are integers ): $x+a$

Let $f(x) = x+a$. Accordingly, $f(x+h) =x+h+a$
By first principle,
$f'(x) \lim\limits_{ h \to 0} \large\frac{f(x+h)-f(x)}{h}$
$= \lim\limits_{ h \to 0} \large\frac{x+h+a-x-a}{h}$
$= \lim\limits_{ h \to 0} \bigg( \large\frac{h}{h}\bigg)$
$= \lim\limits_{ h \to 0} (1)$
$= 1$