Calculați:
[tex] \sqrt{11} - 3.12 + ( - \sqrt{11}) + 3.12 - 1 [/tex]
[tex] \frac{12}{5} + \sqrt{21} + 3 - 2\frac{2}{5} + ( - \sqrt{21} )[/tex]
[tex] - 6 + \sqrt{24} + 0.72 - 2\sqrt{6} + 5.28[/tex]

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