Rút gọn: B = 2^18.3^12.5^2/4^10.9^6.125; C = 13.128-13.28/26.134+26.(-34)

bài 1 rút gọn
a, B=2^18.3^12.5^2/4^10.9^6.125
b, C=13.128-13.28/26.134+26.(-34)
c, D=2x-4/-3x+6
d, K=(-2)^21.3^18.(-5)^25/9^20.(-3)^19.5^25