a x 1 = a
1 x a = a
b : 1 = b
b : b = 1
m : 1 x 1 = m
m x 1 : 1 = m
m : m x 1 = 1
\(a\times1=a\)
\(1\times a=a\)
\(b\div1=b\)
\(b\div b=1\)
\(m\div1\times1=m\)
\(m\times1\div1=m\)
\(m\div m\times1=1\)
a x 1 = a b : 1 = b m : 1 x 1 = m
1 x a = 1 b : b = 1 m : m x 1 = 1
m : m x 1 =1
tk mk nha bn ^^
ax1=a b:1=b m:1x1=m
1xa=a b:b=1 mx1:1=m
m:mx1=1
a x 1 = a
1 x a = a
b : 1 = b
m : 1 x 1 = m
m x 1 : 1 = m
b : b = 1
m : m x 1 = 1