Сократите дроби 1)4-√c / c-16 2)3x^2 +7x-6 / 4-9x^2 - вопрос №7706398141623276492 от Keneke 07.11.2020 17:02

Question

Математика: Сократите дроби 1)4-√c / c-16 2)3x^2 +7x-6 / 4-9x^2

Keneke · Answer

(4-√с) / (с-16) = -(√с-4) / ((√с)² - 4²) =
= - (√с-4)/ ( (√с-4)(√с+4)) =
= - 1/(√с+4)

(3х²+7х-6) / (4-9х²) = (3х²+9х -2х -6) / (2² - (3х)² ) =
= (3х (х+3) -2(х+3)) / (2-3х)(2+3х) =
= ( (3х-2)(х+3) ) / ( -(3х-2)(2+3х) ) =
= - (х+3)/(3х+2)