Question

Na dziś.!! Wzory skróconego mnożenia.

Oblicz sprytnie:

37 x 43=

53[do 2] x 47[do 2]

Answer 1

37 x 43 = (40 - 3) x (40 + 3) = 40^2 - 3^2 = 1600 - 9 = 1 591

 

53^2 x 47^2 = (50 + 3)^2 x (50 - 3)^2 = [ (50 + 3)x(50 - 3) ]^2 = [ 50^2 - 3^2 ]^2 = [ 2500 - 9 ]^2 = 2491^2 = 2491 x 2491 = 6 205 081