Inainte de radical din 3 mai este un radical?
[tex] \sqrt{a-\sqrt{b} } = \sqrt{ \frac{a+c}{2} } - \sqrt{ \frac{a-c}{2} }, c^{2} = a^{2} -b[/tex]\sqrt{3- \sqrt{8} } [/tex]
[tex] c^{2} =9-8 => c=1[/tex]
[tex] \sqrt{ \frac{3+1}{2} } - \sqrt{ \frac{3-1}{2} }= \sqrt{2} -1
[/tex]
\sqrt{a+\sqrt{b} } = \sqrt{ \frac{a+c}{2} } + \sqrt{ \frac{a-c}{2} }, c^{2} = a^{2} -b
[tex] \sqrt{9+4 \sqrt{2} }
[/tex]
[tex]c ^{2} =81-32=> c=7[/tex]
[tex] \sqrt{ \frac{9+7}{2} }+ \sqrt{ \frac{9-7}{2} } = 2 \sqrt{2} +1[/tex]
