Hola

u = x^2 + 6 x

du = (2 x + 6) dx = 2 (x + 3) dx

(x + 3) dx = (1/2) du

∫(x+3)dx / (x² +6x)⅓ = (1/2) ∫ du / u^(1/3)

∫(x+3)dx / (x² +6x)⅓ = (1/2) ∫ u^(-1/3) du

∫(x+3)dx / (x² +6x)⅓ = (1/2) (1/(2/3)) u^(2/3) + C

∫(x+3)dx / (x² +6x)⅓ = (3/4) u^(2/3) + C

∫(x+3)dx / (x² +6x)⅓ = (3/4) (x^2 + 6x)^(2/3) + C

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∫(x+3)dx / (x² +6x)^(⅓) = 3/4 (x (x+6))^(2/3) + C

https://www.youtube.com/watch?v=Y5zCUpQy6Rw

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