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=2/5*t^5-4/3*t^3+C,
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=â«xâ(x+2)d(x+2),
=2/3â«xd(x+2)^(3/2),
=2/3*x(x+2)^(3/2)- 2/3â«(x+2)^(3/2)dx,
=2/3*x(x+2)^(3/2)- 4/3â«(x+2)^(3/2)d(x+2),
=2/3*x(x+2)^(3/2)- 4/15*(x+2)^(5/2)+C,
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A=â«xâ(x+2)dx,
=(1/2)â«â(x+2)dx^2,
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=(1/2)x^2â(x+2)-(1/4)â«x^2/â(x+2)dx,
=(1/2)x^2â(x+2)-(1/4)â«[x(x+2)-2*(x+2)+4]/â(x+2)dx,
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=(1/2)x^2â(x+2)-(1/4)A+1/2â«â(x+2)dx-â«dx/â(x+2),
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A=(2/5)x^2â(x+2)+2/5â«â(x+2)d(x+2)-8/5â(x+2),
A=(2/5)x^2â(x+2)+4/15(x+2)^(3/2)-8/5*â(x+2)+Cã
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