Question

Помогите решить ур-ие)))

Answer 1

1/tgx = t
t^2+9t+8=0
t1= -8
t2= -1
1/tgx = -8
tgx = -1/8
x = arctg... + pn

1/tgx= -1
tgx = -1
x = arctg p/4 + pn