Решите уравнение:
5/cosx=5tgx+4cosx

5/cosx=5sinx/cosx+4cosxcosx≠05=5sinx+4cos²x5-5sinx-4+4sin²x=0sinx=a4a²-5a+1=0D=25-16=9a1=(5-3)/8=1/4⇒sinx=1/4⇒x=(-1)^n*arcsin1/4+πn,n∈za2=(5+3)/8=1⇒sinx=1⇒x=π/2+2πn,n∈z