The length of one arch of sine curve is .
Arc length of the curve in the interval
is
.
Consider the curve is .
Apply derivative on each side with respect to .
.
Substitute and
in
.
.
The length of one arch of cosine curve is .
Arc length of the curve in the interval
is
.
The curve is .
Apply derivative on each side with respect to .
.
Substitute and
in
.
.
Substitute .
Consider .
Apply derivative on each side with respect to .
If then
.
If then
.
Substitute all the values in .
Therefore, the length of one arch of sine curve is equal to the length of one arch of cosine curve.
\The length of one arch of sine curve is equal to the length of one arch of cosine curve.