الحيل الرياضيات

الحيل الرياضياتr:

✦ x * y

✦ x * 11

✦ x * x

x = 15, 25, 35, 45, 55, 65 ..

✦ x * 5

✦ x * y

x,y = 10 ~ 19

✦ x * x

x = 11 ~ 99

✦ x1x2 * y1y2

x1 = y1 = 1 ~ 9, x2 + y2 = 10

23 * 27, 59 * 51, 37 * 33, 68 * 62 ..

✦ x * x

x = 50 ~ 59

✦ x * x

x = 40 ~ 49

✦ x * y

x,y = 11, 21, 31, 41, 51, 61, 71, 81, 91

✦ x * x

x = 100 ~ 109

✦ ......................