Consider the following integral.

${\displaystyle \underset{\phantom{}}{\overset{\phantom{}}{}}}cos(4x)dx$

Given the substitution $u=4x,$ find $du.$

$du=(,)dx$

Rewrite the given integral in terms of $u.$

${\displaystyle \underset{\phantom{}}{\overset{\phantom{}}{}}}()du$

Evaluate the integral by making the given substitution. $($Use $C$ for the constant of integration.$)$

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