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數(shù)學(xué)之美不僅在于其抽象的優(yōu)雅，還在于其建模和解決現(xiàn)實(shí)世界問(wèn)題的深刻能力。

I never make the mistake of arguing with people for whose opinions I have no respect.

You can’t go back and change the beginning, but you can start where you are and change the ending.