Стригонометрий (5sinx-3)/(5cosx-4)=0

(5sinx-3)/(5cosx-4)=0;⇒(5sinx-3)=0;(5cosx-4)≠0;
5sinx=3;⇒sinx=3/5;⇒x=(-1)ⁿarcsin3/5 +kπ;k∈Z;
5cosx≠4;⇒cosx≠4/5;⇒x≠⁺₋arccos4/5+2kπ;k∈Z;