[((5^x) -1) * tg (3x)^2] * [ sqrt(1-6x^3) +1]
(5^x) -1) ~ xln5
tg (3x)^2 ~ 3x^2

Тогда: [((5^x) -1) * tg (3x)^2] * [ sqrt(1-6x^3) +1] \ - 6x^3 =
= 3x^3 ln5 * [ sqrt(1-6x^3) +1] \ - 6x^3 =
= -ln5 * [ sqrt(1-6x^3) +1] \ 2 =
= -2Ln5\2=
= Ln5

Так?