Answer:
Step-by-step explanation:
tan(3x)+1=0
⇔tan3x=-1
⇔tan3x=tan([tex]\frac{-\pi }{4}[/tex])
⇔3x=[tex]\frac{-\pi }{4}[/tex]+k[tex]\pi[/tex]
⇔x=[tex]\frac{-\pi }{12}[/tex]+[tex]\frac{k\pi }{3}[/tex]
=> tan (3x)=-1
=> 3x = −π/4+k.π,k∈Z
=> x= −π/12+k.π/3,k∈Z
