а) 5x² - 125 = 5(x² - 25) = 5(х-5)(х+5)
б) 64 - 4y² = 8² - (2у)² = (8-2у)(8+2у)
в) ax² - ay² = а(х² - у²) = а(х-у)(х+у)
г) x³ - xy² = х(х² - у²) = х(х-у)(х+у)
д) (x+y)² - z² = (х+у-z)(x+y+z)
е) 81 - (a + 2b)² = 9² - (a + 2b)² = (9-a-2b)(9+a+2b)
ж) (a + 2b)² - (a - 2b)² = (a+2b-a+2b)(a+2b+a-2b) = 4b · 2a = 8ab
з) (c + d)² - (2c + 3d)² = (c+d-2c-3d)(c+d+2c+3d) = (-c-2d)(3c+4d) =
= -(c+2d)(3c+4d)
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а) 5x² - 125 = 5(x² - 25) = 5(х-5)(х+5)
б) 64 - 4y² = 8² - (2у)² = (8-2у)(8+2у)
в) ax² - ay² = а(х² - у²) = а(х-у)(х+у)
г) x³ - xy² = х(х² - у²) = х(х-у)(х+у)
д) (x+y)² - z² = (х+у-z)(x+y+z)
е) 81 - (a + 2b)² = 9² - (a + 2b)² = (9-a-2b)(9+a+2b)
ж) (a + 2b)² - (a - 2b)² = (a+2b-a+2b)(a+2b+a-2b) = 4b · 2a = 8ab
з) (c + d)² - (2c + 3d)² = (c+d-2c-3d)(c+d+2c+3d) = (-c-2d)(3c+4d) =
= -(c+2d)(3c+4d)
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к)