Yeah, we generally consider math to be a separate subject from science so this sounds weird.
Perhaps: "Mathematics is an important field."
I asked my Indonesian friend. She says "subject" can also be used as a translation for "ilmu".
Memanggil hal yang bukan pengetahuan alam “science,” itu aneh; menurut saya, “discipline” adalah terjemah yang paling benar.
Mathematics, Science and Technology (MST) - these are separate fields of study.
"Mathematics is important knowledge"should be accepted.
Agree. That's what I wrote, too.