Question

VREAU DOAR 3 SUBPUNCTE REZOLVATE.ATENTIE,FARA EX 9.URGENTTTT​

Answer 1

1. a) $\sqrt{6^{2} } = \sqrt{36} =6$

b)$\sqrt{(-5)^{2} }=\sqrt{25} =5$

c)(nu se vede 3 la ce putere e)

2.a)$3\sqrt{5} +\sqrt{5}=4\sqrt{5}$

b)$3\sqrt{5} -\sqrt{5} =2\sqrt{5}$

c)$3\sqrt{5} *\sqrt{5} =3*5=15$

3.a)$\sqrt{3^{4} } =3^{2} =9$

b)$(-\sqrt{2} )^2=2$

c)$(-\sqrt{2} )^3=-2\sqrt{2}$

4.a)$3/\sqrt{5} =3\sqrt{5} /5$

b)$7/\sqrt{3} =7\sqrt{3} /3$

c)$-5/3\sqrt{2} =-5\sqrt{2} /3*2=-5\sqrt{2} /6$

5.a)$5\sqrt{18} +3\sqrt{2} -\sqrt{98} =5*3\sqrt{2} +3\sqrt{2} -7\sqrt{2} \\=15\sqrt{2} +3\sqrt{2} -7\sqrt{2} \\=11\sqrt{2}$

b)$7\sqrt{5} +2\sqrt{125} -\sqrt{20} =7\sqrt{5} +2*5\sqrt{5} -2\sqrt{5} \\=15\sqrt{5}$

c)$4\sqrt{7} -3\sqrt{28} +\sqrt{7} =\\4\sqrt{7} -3*2\sqrt{7} +\sqrt{7} =5\sqrt{7} -6\sqrt{7} =\\=-\sqrt{7}$

6.a)$6/\sqrt{3} +2\sqrt{3} -\sqrt{27} =\\2\sqrt{3}+2\sqrt{3} -3\sqrt{3} =\sqrt{3}$

b)$10/\sqrt{2} +12\sqrt{2} /\sqrt{6} -2\sqrt{50} =\\5\sqrt{2} +4\sqrt{3} -10\sqrt{2} =4\sqrt{3} -5\sqrt{2}$

c)$5/\sqrt{2} +7/3\sqrt{2} -2\sqrt{3} /\sqrt{6}=\\ 5\sqrt{2} /2+7\sqrt{2} /6-\sqrt{2} =\\15\sqrt{2} +7\sqrt{2} -6\sqrt{2} =16\sqrt{2}$

7.a)$\sqrt{6*8} =\sqrt{2*3*2^{3} }=4\sqrt{3}$

b)$\sqrt{10*15} =\sqrt{2*5*3*5} =5\sqrt{6}$

c)$\sqrt{\sqrt{3} *\sqrt{27} } =\sqrt{\sqrt{3}*\sqrt{3^{3} } } =\\=\sqrt{3^{2} } =3$

8.a)$x^{2} =25\\x1=5\\x2=-5$

b)$x^{2} =-16\\x1=4i\\x2=-4i$

c)$3x^{2} =0\\x=0$