[lax4ever]

1) It is OK to not know something. No one knows everything. Those who expect you to know everything have unrealistic expectations.

2) Acknowledging your lack of knowledge and weak points is a good and healthy thing. No one is perfect and you have no reason to expect yourself to be perfect and it helps you set goals for yourself.

3) It is not OK to refuse to overcome said lack of knowledge, especially in a subject where you need it for your career goals.

4) The beauty of the world wide web is that there are many places to find answers to arithmetic problems. If you don't know something, ask/search. Either a professor/instructor or find an answer online from a reputable source.

5) Keep on learning. Seriously, never stop in your attempts to learn. Then look back in 1/3/5/10 years time and see just how far you have come.