[tex]sin(4x)= \dfrac{3}{4} [/tex]
[tex]4x=sin^-^1( \dfrac{3}{4}), \pi -sin^-^1( \dfrac{3}{4}) [/tex]
Since sin is a periodic function, add the periodicity.
[tex]4x=2\pi n+sin^-^1 ( \dfrac{3}{4} ) ,nEZ
[/tex]
[tex]4x=2\pi n-sin^-^1 ( \dfrac{3}{4} ) ,nEZ [/tex]
[tex]x= \dfrac{2\pi n+sin^-^1 ( \dfrac{3}{4} ) }{4}, nEZ[/tex]
[tex]x= \dfrac{2\pi n+ \pi -sin^-^1 ( \dfrac{3}{4} ) }{4}, nEZ[/tex]
