By the Apollonius theorem, in any triangle, the lengths $m_a$ $m_b$ $m_c$ of the medians of opposing the the sides $a$ $b$ $c$ respectively, are $$m_a = \frac{1}{2}\sqrt{2b^2+2c^2-a^2},$$ $$m_b = \frac{1}{2}\sqrt{2c^2+2a^2-b^2},$$ $$m_c = \frac{1}{2}\sqrt{2a^2+2b^2-c^2}.$$