evaluate the indefinite integral ∫(x-2)e^(x^2-4x-3)dx
Let \(u=x^2-4x-3\)
i dont understand how to do the u sustitution
see if this helps https://www.khanacademy.org/math/integral-calculus/integration-techniques/u_substitution/v/u-substitution
@ganeshie8 is this correct?
what about \(u = (x-2)^2\)
differentiate your answer and see if you get back the integrand
\[\dfrac{d}{dx} \left(\color{red}{\dfrac{1}{2}e^{x^2-4x-3}+C}\right) = ?\]
xe^(x^2)-4
du is 2x-4.... what do i do with the (X-2) then?
2x -4 = 2( x -2 )
2e^(x^2-4x-3)+C
u= x^2-4x-3 du = (2x -4) dx du = 2( x-2) dx du /2 = (x-2) dx
$$ \large \int (x-2) e^{x^2-4x-3} dx \\ = \large \int e^{x^2-4x-3} (x-2)dx \\ = \large \int e^{u}~ \frac{du}{2} = \frac 1 2 \large \int e^{u}~ du $$
1/2 e^(x^2-4x-3) + C
thats correct
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