Предмет: Алгебра, автор: Rassomachin

Докажите тождество: 2x(2-3x)(3x+2)=8x-18x         18х(в кубе)

Ответы

Автор ответа: Аничка1990
0

левая часть по формулам равна (разница квадратов)

2х(4-(3х)(кв))=8х-18х(куб)

раскрываем скобки

8х-18х(куб)=8х-18х(куб)

0=0

доказано

Автор ответа: dtnth
0

используя формулу разности квадратов:

2x(2-3x)(3x+2)=2x((2^2-(3x)^2))=2x(4-9x^2)=2x*4-2x*9x^2=8x-18x^3

, что и требовалось доказать

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