How to learn certain Maths to understand machine Learning papers? I have done the deeplearning.ai course on deep learning. But I cannot Understand equations like 

minGmaxDV(D,G)=Ex∼pdata(x)[logD(x)]+Ez∼pz(z)[log(1−D(G(z)))]


What kind of Maths am I am supposed to learn? I know Calculus basic Multivariable Calculus and Linear Algebra. So should I learn Probability (Advance probability maybe)?
As Elias mentioned, the expectations are related to random variables and you would be good to go if you know about conditional probability, multivariate probability, joint and marginal distributions. I would suggest you take a course that has a syllabus on the lines of https://secure.oregonstate.edu/ap/cps/documents/view/134169.