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Denebel
how do I integrate (3)/(x^2 + 9) dx using partial fractions? Thank you.
you don't need partial fractions .. assume x = 3 tany .. then substitute .. you would get get 1/3 taninv(x/3) as your answer...
srry u wd get taninv(x/3) as answer..
what happens to the 1/3?
..And how can you know to assume a tan. function?
you can assume the tan function because you change the coordinates. .. see integration is nothing but area under the curve .. when you integrate f(x) in x you find area under the curve for when f(x)is plotted in xy plane.. when i write x = tany I am calculating area for the same graph in a different plane .. value of my area would remain the same... I hope this helps
Kind of, can you elaborate some more?
check this website ... http://www.sosmath.com/calculus/integration/substitution/substitution.html