Calculate spiral length: Calculate the length of the spiral using the integral formula for polar coordinates: L=∫r2+(dθdr)2dθ.
Find dθdr: First, find dθdr. Since r=θ, dθdr=dθdθ=1.
Plug into integral formula: Now, plug r=θ and dθdr=1 into the integral formula: L=∫02θ2+12dθ.
Simplify integral: Simplify the integral: L=∫02θ2+1dθ.
Use trigonometric substitution: Now we need to solve the integral. This is a bit tricky, but we can use a trigonometric substitution or look up the integral in a table.
Change limits of integral: Let's use a trigonometric substitution. Set θ=tan(u), then dθ=sec2(u)du.
Simplify integral with identity: When θ=0, u=0, and when θ=2, u=arctan(2). So we need to change the limits of the integral.
Complex integral solution: The integral becomes L=∫0arctan(2)tan2(u)+1sec2(u)du.
Final integral result: Simplify the integral using the identity tan2(u)+1=sec2(u): L=∫0arctan(2)sec3(u)du.
Final integral result: Simplify the integral using the identity tan2(u)+1=sec2(u): L=∫0arctan(2)sec3(u)du.This integral is still complex, but we can look it up or use a reduction formula. The result is L=[21sec(u)tan(u)+21ln∣sec(u)+tan(u)∣]0arctan(2).
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