1 ∨ a*•a* ∨ a   ≤   a* a* ≤ (a ∨ b)* (a → a)*   ≤   a → a The first equation can be broken out into three equations, 1 ≤ a*, a*•a* ≤ a*, and a ≤ a*.
1 ∨ a*·a* ∨ a ≤ a* a* ≤ (a∨b)* (a → a)* ≤ a → a 第一个等式可分解为三个等式 1 ≤ a*, a*·a* ≤ a* 和 a ≤ a*。