Question 1052561
Use your parentheses.
Is it {{{y=sin^4(3x)/(3x)}}}??
Use the quotient rule.
{{{dy/dx=(3x(4*sin^3(3x)cos(3x)*3)-sin^4(3x)*3)/(3x)^2}}}
{{{dy/dx=(12x*sin^3(3x)cos(3x)-sin^4(3x))/(3x^2)}}}