а)4m² – 4n²= (2m-2n)(2m+2n)
б) 7y² – 7 = 7(y²-1)
в) y³ – 25y = y(y²-25)
г)5b² – 10b +5 = 5(b²-2b+1) = 5·(b-1)²
д) -3m² – 6mn – 3n² = -3(m²+2mn+n²) = -3·(m+n)²
а)4m² – 4n²= (2m-2n)(2m+2n)
б) 7y² – 7 = 7(y²-1)
в) y³ – 25y = y(y²-25)
г)5b² – 10b +5 = 5(b²-2b+1) = 5·(b-1)²
д) -3m² – 6mn – 3n² = -3(m²+2mn+n²) = -3·(m+n)²