"If you able to solve the problems in MATHS, then you also able to solve the problems in your LIFE" (Maths is a great Challenger)
As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality.
M4Math helped me a lot.
Thanks m4 maths for helping to get placed in several companies. I must recommend this website for placement preparations.