是∫x^2(arcsinx)^2 /√(1-x^2) dx从-1到1的积分
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是∫x^2(arcsinx)^2 /√(1-x^2) dx从-1到1的积分
是∫x^2(arcsinx)^2 /√(1-x^2) dx从-1到1的积分
是∫x^2(arcsinx)^2 /√(1-x^2) dx从-1到1的积分
∫(-1->1) [x^2(arcsinx)^2 /√(1-x^2) ]dx
let
x= siny
dx=cosydy
x=-1, y=- π/2
x=1, y=π/2
∫(-1->1) [x^2(arcsinx)^2 /√(1-x^2) ]dx
=∫(-π/2->π/2) [y^2.(siny)^2 ]dy
=2∫(0->π/2...
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∫(-1->1) [x^2(arcsinx)^2 /√(1-x^2) ]dx
let
x= siny
dx=cosydy
x=-1, y=- π/2
x=1, y=π/2
∫(-1->1) [x^2(arcsinx)^2 /√(1-x^2) ]dx
=∫(-π/2->π/2) [y^2.(siny)^2 ]dy
=2∫(0->π/2) [y^2.(siny)^2 ]dy
=∫(0->π/2)y^2. ( 1- cos2y) dy
= [y^3/3](0->π/2) -(1/2) ∫(0->π/2) y^2 d(sin2y)
=(π)^3/24 - (1/2)[ y^2.sin2y](0->π/2) + ∫(0->π/2) y.(sin2y) dy
=(π)^3/24 -(1/2) ∫(0->π/2) y.d (cos2y)
=(π)^3/24 -(1/2) [y.(cos2y)](0->π/2) + (1/2) ∫(0->π/2) cos2y.dy
=(π)^3/24 +π/4 + (1/4)[ sin2y](0->π/2)
=(π)^3/24 +π/4
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