※ 引述《icu (這是可以說的秘密)》之銘言:
: 5 6x^2-22x+18
: ∫-----------------dx ans : ln24
: 4 x^3-6x^2+11x-6
5 6x^2-22x+18
∫-----------------dx
4 x^3-6x^2+11x-6
5 6x^2-22x+18
= ∫-----------------dx
4 (x-1)(x-2)(x-3)
5 1 2 3
= ∫----- + ----- + -----dx
4 x-1 x-2 x-3
5
= (ln|x-1| + 2ln|x-2| + 3ln|x-3|)|
4
= (ln4 + 2ln3 + 3ln2) - (ln3 + 2ln2 + 3ln1)
= ln4 + ln3 + ln2
= ln24
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