2. Suppose that when n=x, the above formula also holds, 2x >；; x^2

Then when n=x+ 1, 2n = 2 (x+1) = 2 * (2x) = 2x+2x > x 2+x 2.

n^2=(x+ 1)^2=x^2+2x+ 1

X 2-2x-1= (x-1) 2-2 This is not always greater than 0.

Unable to get 2 n > n^2.

I can't prove it anymore.

This is how mathematical induction is proved. I feel that high school likes to do this topic best, and it is worth it. Getting started is easy and easy.