Hi,
No. The memory cannot be upgraded.
According to the [https://www.asus.com/ph/2-in-1-PCs/ASUS_Transformer_Book_T100TA/specifications/|specifications] it has 2GB of memory. They don’t specify that it is ''onboard'' memory but they do on other models such as the T100TAL so this would be the same.
Here’s a [https://www.youtube.com/watch?v=RM_fIU_Bb_o|video] that shows how to replace a faulty USB port in the laptop. I realize that this is not what you’re asking about, but it is handy as it gives a look at the motherboard (both sides) and there are no removable RAM modules to be seen.