The theory on well - posedness and regularity of solutions to such class of degenerate problems , plays a crucial role in the above fields . anyway , such equations are deserved to be investigated vastly 進(jìn)而通過解常微分方程,可以得到弱解關(guān)于退化方向的一階導(dǎo)數(shù)的一種積分表達(dá)式,從而在兩種不同情形下建立了兩個(gè)基本引理。