what is the integral of (2x+5)/(2x-5)dx??
Thanks =)
Thanks =)
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Hello,
∫ [(2x + 5) /(2x - 5)] dx =
being numerator and denominator of the same order, let's subtract and add 5 in the numerator:
∫ [(2x - 5 + 5 + 5) /(2x - 5)] dx =
∫ {[(2x - 5) + 10] /(2x - 5)} dx =
(distributing and simplifying)
∫ {[(2x - 5) /(2x - 5)] + [10 /(2x - 5)]} dx =
∫ {1 + [10 /(2x - 5)]} dx =
(splitting into two integrals)
∫ dx + ∫ [10 /(2x - 5)] dx =
x + ∫ [10 /(2x - 5)] dx =
let's pull 5 out of the remaining integral, obtaining in the numerator the derivative of the denominator:
x + ∫ [5(2) /(2x - 5)] dx =
x + 5 ∫ [2 /(2x - 5)] dx =
x + 5 ∫ d(2x - 5) /(2x - 5) =
x + 5 ln |2x - 5| + C
the answer is:
∫ [(2x + 5) /(2x - 5)] dx = x + 5 ln |2x - 5| + C
I hope it helps
∫ [(2x + 5) /(2x - 5)] dx =
being numerator and denominator of the same order, let's subtract and add 5 in the numerator:
∫ [(2x - 5 + 5 + 5) /(2x - 5)] dx =
∫ {[(2x - 5) + 10] /(2x - 5)} dx =
(distributing and simplifying)
∫ {[(2x - 5) /(2x - 5)] + [10 /(2x - 5)]} dx =
∫ {1 + [10 /(2x - 5)]} dx =
(splitting into two integrals)
∫ dx + ∫ [10 /(2x - 5)] dx =
x + ∫ [10 /(2x - 5)] dx =
let's pull 5 out of the remaining integral, obtaining in the numerator the derivative of the denominator:
x + ∫ [5(2) /(2x - 5)] dx =
x + 5 ∫ [2 /(2x - 5)] dx =
x + 5 ∫ d(2x - 5) /(2x - 5) =
x + 5 ln |2x - 5| + C
the answer is:
∫ [(2x + 5) /(2x - 5)] dx = x + 5 ln |2x - 5| + C
I hope it helps