Homework Statement
Evaluate the limits that exist:
lim x->0 of \frac{1-cos4x}{9x^{2}}
Homework Equations
lim x->0 \frac{1-cosax}{ax} = 0
The Attempt at a Solution
so far I've got this
\frac{4x}{9x^{2}}\frac{1-cos4x}{4x}
The second part has a limit of 0 but I don't know what to...