Integral of a vector valued function

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I came across this integral of a vector valued function.
[tex]\int \mathbf A(t) \vec{w(t)} dt = \int \mathbf B(t)[/tex].
I want to isolate [itex]\vec{w(t)}[/itex] and so I multiply by [itex]\left (\int \mathbf A(t) dt \right)^{-1}[/itex] on both sides.
[tex]\left (\int \mathbf A(t) dt \right)^{-1} \int \mathbf A(t) \vec{w(t)} dt = \left (\int \mathbf A(t) dt\right)^{-1} \int \mathbf B(t) dt[/tex]

I thought the correct form would be
[tex]\int \vec{w(t)} dt = \left (\int \mathbf A(t) dt\right)^{-1} \int \mathbf B(t) dt[/tex].

But it turns out I get the right answer if I take
[tex]\vec{w(t)} = \left (\int \mathbf A(t) dt \right)^{-1} \int \mathbf B(t) dt[/tex].

Can anyone show why the second form is correct?
 
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Both formulas are wrong. Check it with ##\omega(t)=t^2## and ##A(t)=e^t##. All we have is the integration by parts: ##\displaystyle{\int } A(t)\omega(t)dt = \left(\int A(t)dt\right) \omega(t) - \int \left(\int A(t)dt\right)\omega'(t)dt##