刚做了单向视频面试，6题，每题5分钟。后面五题是选择题。\n\n1. Describe the project that you are most proud of.\n2. Derivative of x^x\n3. Y and M are 4D subspace of a 7D vector space X. The intersection of Y and M cannot be 0/1/2/3 dimension (choose one).\n4. What is the smallest a that makes the following matrix semi-definite?\n 1, a, a\n a, 1, a\n a, a, 1-baidu 1point3acres\n5. Three uniform random numbers between (0,1). The probability that the second largest number is smaller than 2/3\n. From 1point 3acres bbs\n\n6. Expectation E(e^(tX)) = e^(t^2). What is E(X^2)?\n\n