(sin5x//cosx)=(sinx//cos5x) решите уравнение - вопрос №579126555 от alizhanayanaoxi717 31.07.2020 03:19

Question

Математика: (sin5x//cosx)=(sinx//cos5x) решите уравнение

alizhanayanaoxi717 · Answer

(sin5x//cosx)=(sinx//cos5x) sin5x·cosx-cos5x·sinx/sinx·cosx=sinx·cos5x-cosx·sin5x/sin5x·cos5x 2sin4x/sin2x=-2sin4x/sin10x 1/sin2x=-1/sin10x, sin2x=-sin10x sin2x+sin10x=0 sin2x+sin10x=2sin(2x+10x)/2·cos(2x-10x)/2=0 sin6x·cos4x=0 6x=πn, 4x=πn. n∈z x=πn/6 , x=πn/4, n∈z...