Question

Довести тотожность:
(3m-4)(7n²
-3n-5)+(4-3m)(7n²-3n-3)=8-6m
ДАЮ 42 БАЛЛА!

Answer 1

(3m-4)(7n²-3n-5)+(4-3m)(7n²-3n-3)=
=(3m-4)(7n²-3n-5)-(3m+4)(7n²-3n-3)=
=(3m-4)(7n²-3n-5-7n²+3n+3)=
=(3m-4)*(-2)=
=8-6m

Answer 2

спасибо