Question

tính abcd-dcba biết a-d=5  b-c=3

Answer 1

ai nhanh nhất mình like nhé:3

tks

Answer 2

\(\overline{abcd}-\overline{dcba}\\ =1000a+100b+10c+d-1000d-100c-10b-a\\ =999a +90b-90c-999d\\ =999\left(a-d\right)+90\left(b-c\right)\\ =999\cdot5-90\cdot3=4725\)