237²+2*237*163+161²=(237+161)²=398²=158404
Там получается бесконечность
{ x - y =π/2 ; cosx - cosy =√2 ⇔ { x - y =π/2 ; - 2sin(x-y)/2*sin(x+y)/2 =√2 .
{ x - y =π/2 ; - 2sinπ/4*sin(x+y)/2 =√2 .
- 2sinπ/4*sin(x+y)/2 =√2 ;
-2*(1/√2)*sin(x+y)/2 =√2 ;
sin(x+y) = -1;
x+y = π+2π*k , k∈ Z .
{x+y = π+2π*k , k∈ Z ; x-y =π/2 ⇔ {2x =π+2π*k +π/2 ; 2y = π+2π*k -π/2.
{x =3/4π+ π*k ; y = π/4+ π*k , k ∈Z.
ответ : x =3/4π+ π*k , k ∈Z , y = π/4+ π*k , k ∈Z.