Math

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Evaluate the integral of x * sqrt(x-1) from [1,2].


I let u=x-1 and du=1*dx, but then I can't get rid of the x to start integrating?

The answer in the book is 16/15.

  • Math -

    Let
    u^2 = x-1
    2u du = dx
    x = u^2+1

    ∫x√(x-1) dx
    = ∫(u^2+1)(u)(2u du)
    ...

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