[tex]2sin7x+ \sqrt{2} = 0 [/tex]
[tex]sin7x = - \frac{ \sqrt{2} }{2} [/tex]
[tex]7x = (-1)^k arcsin(- \frac{ \sqrt{2} }{2}) + kpi
[/tex]
[tex]7x = (-1)^{k+1} \frac{ \pi }{4} + kpi[/tex]
[tex]x = (-1)^{k+1} \frac{ \pi }{28} + \frac{kpi}{7} [/tex], unde k este un numar intreg
