Question 442657
That's easy.

Just look at the intersection points of the unit circle {{{u^2 + v^2 = 1}}} and the line u = v, which are the points ({{{1/sqrt(2)}}},{{{1/sqrt(2)}}}) and ({{{-1/sqrt(2)}}}, {{{-1/sqrt(2)}}}), which happen when {{{s = pi/4}}} and {{{s = (5pi)/4}}}.