1) ( 5M - 1)^2 = 25M^2 - 10M + 1
2) ( 5M + 3)^2 = 25M^2 + 30M + 9
3) ( 5M - 3)*( 25M^2 + 30M + 9 ) = 125M^3 + 150M^2 + 45M - 75M^2 - 90M - 27 =
= 125M^3 + 75M^2 - 45M - 27
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4) 25M^2 - 10M + 1 - 125M^3 - 75M^2 + 45M + 27 =
= - 125M^3 - 50M^2 + 35M + 27 ( Ответ )