You are asked to derive expressions for the average rates of change of the functions $\sin x, \cos x,$ and $\tan x$
In each case, assume that the interval is $[x, x+h] .$ (The results are used in calculus in the study of derivatives.)
Let $T(x)=\tan x .$ Show that
$$
\frac{\Delta T}{\Delta x}=\frac{\tan h}{h} \cdot \frac{\sec ^{2} x}{1-\tan h \tan x}
$$