# Is this a theorem?

Algebra Level 4

If $$x_1 , x_2 , x_3 , \ldots , x_n$$ are any real number and n is any positiv integer, then

A. $$n \displaystyle\sum_{i = 1}^{n} x_i^2 < \left( \displaystyle\sum_{i=1}^n x_i\right)^2$$
B. $$\displaystyle\sum_{i = 1}^{n} x_i^2 \geq \left( \displaystyle\sum_{i=1}^n x_i\right)^2$$
C. $$\displaystyle\sum_{i = 1}^{n} x_i^2 \geq n\left( \displaystyle\sum_{i=1}^n x_i\right)^2$$
D. $$\displaystyle\sum_{i = 1}^{n} x_i \leq\left( \displaystyle\sum_{i=1}^n x_i\right)^2$$
E. None of these

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