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Write and simplify, but do not evaluate, an integral with respect to x that gives the length of the following curve on the given interval y=2cos 3x on -- An integral that gives the arc length is a d x (Type exact answers.) Enter your answer in each of the answer boxes.

User DirkNM
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1 Answer

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22 votes

The arc length of
y=2\cos(3x) on the interval
[a,b] is


\displaystyle \int_a^b √(1 + (y')^2) \, dx = \int_a^b √(1 + (-6\sin(3x))^2) \,dx = \boxed{\int_a^b √(1+36\sin^2(3x)) \, dx}

User Artem Khojoyan
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