Question

A circle has a center at `(1 ,2 )` and passes through `(4 ,3 )`. What is the length of an arc covering `pi /4` radians on the circle?

Answer 1

`( sqrt(10) pi ) / 4`

Explanation:

Please check my solution here for a detailed explanation.

Solution
Radius `r = sqrt( (4 - 1)^2 + (3 - 2)^2 ) = sqrt(10)`.
Arc length `S = ( sqrt(10) pi ) / 4`.