(4x2)-(129x2)! -(2-1-)! -(21) =22 5×8÷32 13 +× (2³)÷25 X22÷25 a-2+ 1 a 363 (1) (ab)(a+b)(a+ = 2 - {(at) - (61)*) (+) = (at-b³)(at +61) 2 = (a²)² - (b³)² = a-b (2) (a+b)(a+ =(23)+(63) (a = a+b 300 (2)