1. a) [tex]\sqrt{6^{2} } = \sqrt{36} =6[/tex]
b)[tex]\sqrt{(-5)^{2} }=\sqrt{25} =5[/tex]
c)(nu se vede 3 la ce putere e)
2.a)[tex]3\sqrt{5} +\sqrt{5}=4\sqrt{5}[/tex]
b)[tex]3\sqrt{5} -\sqrt{5} =2\sqrt{5}[/tex]
c)[tex]3\sqrt{5} *\sqrt{5} =3*5=15[/tex]
3.a)[tex]\sqrt{3^{4} } =3^{2} =9[/tex]
b)[tex](-\sqrt{2} )^2=2[/tex]
c)[tex](-\sqrt{2} )^3=-2\sqrt{2}[/tex]
4.a)[tex]3/\sqrt{5} =3\sqrt{5} /5[/tex]
b)[tex]7/\sqrt{3} =7\sqrt{3} /3[/tex]
c)[tex]-5/3\sqrt{2} =-5\sqrt{2} /3*2=-5\sqrt{2} /6[/tex]
5.a)[tex]5\sqrt{18} +3\sqrt{2} -\sqrt{98} =5*3\sqrt{2} +3\sqrt{2} -7\sqrt{2} \\=15\sqrt{2} +3\sqrt{2} -7\sqrt{2} \\=11\sqrt{2}[/tex]
b)[tex]7\sqrt{5} +2\sqrt{125} -\sqrt{20} =7\sqrt{5} +2*5\sqrt{5} -2\sqrt{5} \\=15\sqrt{5} \\[/tex]
c)[tex]4\sqrt{7} -3\sqrt{28} +\sqrt{7} =\\4\sqrt{7} -3*2\sqrt{7} +\sqrt{7} =5\sqrt{7} -6\sqrt{7} =\\=-\sqrt{7}[/tex]
6.a)[tex]6/\sqrt{3} +2\sqrt{3} -\sqrt{27} =\\2\sqrt{3}+2\sqrt{3} -3\sqrt{3} =\sqrt{3}[/tex]
b)[tex]10/\sqrt{2} +12\sqrt{2} /\sqrt{6} -2\sqrt{50} =\\5\sqrt{2} +4\sqrt{3} -10\sqrt{2} =4\sqrt{3} -5\sqrt{2}[/tex]
c)[tex]5/\sqrt{2} +7/3\sqrt{2} -2\sqrt{3} /\sqrt{6}=\\ 5\sqrt{2} /2+7\sqrt{2} /6-\sqrt{2} =\\15\sqrt{2} +7\sqrt{2} -6\sqrt{2} =16\sqrt{2}[/tex]
7.a)[tex]\sqrt{6*8} =\sqrt{2*3*2^{3} }=4\sqrt{3} \\[/tex]
b)[tex]\sqrt{10*15} =\sqrt{2*5*3*5} =5\sqrt{6} \\[/tex]
c)[tex]\sqrt{\sqrt{3} *\sqrt{27} } =\sqrt{\sqrt{3}*\sqrt{3^{3} } } =\\=\sqrt{3^{2} } =3[/tex]
8.a)[tex]x^{2} =25\\x1=5\\x2=-5[/tex]
b)[tex]x^{2} =-16\\x1=4i\\x2=-4i[/tex]
c)[tex]3x^{2} =0\\x=0[/tex]
