The region is given by the following integral:
3
∫ 1/√(x² + 9) dx
0
You can solve this integral by substitution
set x = 3·sinh(z) ←→ z = arsinh(x/3)
→ dx = 3·cosh(z)
∫ 1/√(x² + 9) dx
= ∫ 3·cosh(z) / √(9·sinh²(z) + 9) dz
= ∫ cosh(z) / √(sinh²(z) + 1) dz
because cosh²(z) - sinh²(z) = 1
= ∫ √(sinh²(z) + 1) / √(sinh²(z) + 1) dz
= ∫ 1 dz
= z + c
= arsinh(x/3) + c
Therefore:
3
∫ 1/√(x² + 9) dx
0
= arsinh(1) - arsinh(0)
= arsinh(1)
because arsinh(z) = ln(z + √(z² + 1))
= ln(1 + √2)
= .88137...
2007-07-15 20:32:57
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answer #1
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answered by schmiso 7
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Okay, here it is given that the boundary is from 0 to 3.
Integrate the equation within the boundary:
Integrate from 0 (lower case)to 3(upper case) 1/sqrt(x^2 + 9) =
(x^2 + 9)^(1/2)/ (1/2) from 0 to 3 = 2(x^2+9)^(1/2) from 0 to 3 = 2(sqrt 18 - sqrt 9)= 2sqrt18 - 6
note: 1/ sqrt (x^2+9) = (x^2+9)^(-1/2)
2007-07-15 19:04:30
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answer #2
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answered by cflakez 2
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Integrate the function with limits of 3 and 0.
The function integrates as natural log (x^2+x+9).
At 3, the value is ln 21.
At 0. the value is ln 9.
So the value is ln (21/9) or ln (7/3).
2007-07-15 18:57:07
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answer #3
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answered by cattbarf 7
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why u r troubling with quantity ? basically remedy it via integration initially locate factors on graph as follows :on line y=secx while x=0 ,y=a million,while y=0, x=pi/2 subsequently factors is (0,a million) and (pi/2,0) while x=pi/3, then y =2 subsequently factor is (pi/3,2) now remedy it graphically its effortless if any problem u can use actual graph paper, it wil be much less stressful
2016-11-09 10:38:34
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answer #4
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answered by ? 4
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good luck...
2007-07-15 18:52:31
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answer #5
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answered by G 1
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