am nevoie urgent!!!!​

Răspuns:

[tex] |7 - 5 \sqrt{2} | + \frac{30}{ \sqrt{18} + 6 } = \\ \\ = 5 \sqrt{2} - 7 + \frac{30}{3 \sqrt{2} + 6 } = \\ \\ = 5 \sqrt{2} - 7 + \frac{10}{ \sqrt{2} + 2} = \\ \\ = 5 \sqrt{2} - 7 + \frac{10( {2} - \sqrt{2}) }{2} = \\ \\ = 5 \sqrt{2} - 7 + 5(2 - \sqrt{2} ) = \\ \\ = 5 \sqrt{2} - 7 + 10 - 5 \sqrt{2} = \\ \\ = 10 - 7 = \\ \\ = 3[/tex]

Succes!

|7-[tex]5\sqrt2[/tex]|+[tex]\frac{30}{\sqrt18+6}[/tex] = [tex]5\sqrt2 - 7 + \frac{30}{3\sqrt2+6}[/tex] = [tex]5\sqrt2-7+\frac{30}{3(\sqrt2+2}[/tex] = [tex]5\sqrt2 - 7 + \frac{10}{\sqrt2+2}[/tex]

[tex]5\sqrt2 - 7 - 5(\sqrt2-2)[/tex] = [tex]5\sqrt2 -7-5\sqrt2+10[/tex] = -7+10 = 3

b) Sofia