вправа 480 гдз 7 клас алгебра Бевз
Вправа 480
а) 352 - 152 = (35 - 15)(35 + 15) = 20 • 50 = 1000;
б) 432 - 272 = (43 - 27)(43 + 27) = 15 • 70 = 1050;
в) 1362 - 642 = (136 - 64)(136 + 64) = 200 • 72 = 14400;
г) 51,52 - 49,52 = (51,5 - 49,5)(51,5 + 49,5) = 2 • 101 = 202;
ґ) 21,32 - 1,32 = (21,3 - 1,3)(21,3 + 1,3) = 20 • 22,6 = 452;
д) (3 2/3)2 - (1 1/3)2 = (3 2/3 - 1 1/3)(3 2/3 + 1 1/3) = 2 1/3 • 5 = 7/3 • 5/1 = 35/3 = 11 2/3.
а) 352 - 152 = (35 - 15)(35 + 15) = 20 • 50 = 1000;
б) 432 - 272 = (43 - 27)(43 + 27) = 15 • 70 = 1050;
в) 1362 - 642 = (136 - 64)(136 + 64) = 200 • 72 = 14400;
г) 51,52 - 49,52 = (51,5 - 49,5)(51,5 + 49,5) = 2 • 101 = 202;
ґ) 21,32 - 1,32 = (21,3 - 1,3)(21,3 + 1,3) = 20 • 22,6 = 452;
д) (3 2/3)2 - (1 1/3)2 = (3 2/3 - 1 1/3)(3 2/3 + 1 1/3) = 2 1/3 • 5 = 7/3 • 5/1 = 35/3 = 11 2/3.