6·x/(18·x^3 - 2·x)=
=6·x/(2·x·(3·x + 1)·(3·x - 1))=
=3/((3·x + 1)·(3·x - 1)) con x ≠ 0
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(2·a^5 - a^6)/(a^5 - 4·a^3)=
=a^5·(2 - a)/(a^3·(a + 2)·(a - 2))=
=- a^2/(a + 2) con a ≠ 0 ∧ a ≠ 2
C.E.
18x³-2x≠0
2x(9x²-1)≠0
2x(3x+1)(3x-1)≠0
S: x≠0∧x≠±1/3
a⁵-4a³≠0
a³(a²-4)≠0
a³(a+2)(a-2)≠0
S: a≠0∧a≠±2
6x/2x(3x+1)(3x-1)
3/(3x+1)(3x-1)
(2a⁵-a⁶)/a³(a+2)(a-2)
a⁵(2-a)/a³(a+2)(a-2)
-a²(a-2)/(a+2)(a-2)
-a²/a+2