Recent content by viczhang

Suppose the functions f(t) and g(t) are periodic with periods P and Q, respectively. If the ratio P/Q of their periods is a rational number, show that the sum f(t)+g(t) is a period function. How to prove this?

I am enrolled by Engineering Physics undergrad program in UIUC. My intention to choose this major is to have a ground knowledge in physics and math as well as have some idea of engineering. Since I will definitely go to graduate school so my present puzzle is how well can this major prepare for...