Question

Find limit as subtended angle approaches 0.

Answer 1

What I did was.

\[\large s = r\Theta\]
so
\[\frac{\theta}{2} = \frac{s}{2r}\]

then I know that \[\cos(\frac{s}{2r}) = \frac{r-h}{r}\]

Then I did \[d = r^{2} - (r-h)^{2}\]