Докажите неравенство: a^2 + b^2 - 4ab >= - 2ab

Question

Докажите неравенство: a^2 + b^2 - 4ab >= - 2ab

Answer 1

=-2ab\\(a^{2}-2ab+b^{2})-2ab>=-2ab\\(a-b)^{2}>=0" alt="a^{2}+b^{2}-4ab>=-2ab\\(a^{2}-2ab+b^{2})-2ab>=-2ab\\(a-b)^{2}>=0" align="absmiddle" class="latex-formula">

Comments

Спасибо!