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a)\(\sqrt{7.63}\)=21

b)\(\sqrt{2,5.30.48}\)=60

c)\(\sqrt{0,4.6,4}\)=1,6

d)\(\sqrt{2,7.5.1,5}\)=4,5

a) $\sqrt{7}.\sqrt{63}=\sqrt{7.63}=\sqrt{{\mathrm{7.7.3}}^2}=\sqrt{(7.3{)}^2}=7.3=21$.

b) $\sqrt{2,5}.\sqrt{30}.\sqrt{48}=\sqrt{2,\mathrm{5.30.48}}=\sqrt{\mathrm{25.3.48}}$

$\sqrt{5^2.3.3{.4}^2}=\sqrt{(\mathrm{5.3.4}{)}^2}=\mathrm{5.3.4}=60$.

c) $\sqrt{0,4}.\sqrt{6,4}=\sqrt{0,4.6,4}=\sqrt{0,04.64}$

$=\sqrt{0,2^2{.8}^2}=\sqrt{(0,2.8{)}^2}=0,2.8=1,6$.

d) $\sqrt{2,7}.\sqrt{5}.\sqrt{1,5}=\sqrt{2,\mathrm{7.5.1},5}$

$=\sqrt{3^2.0,\mathrm{3.5.5.0},3}=\sqrt{(3.0,3.5{)}^2}=4,5$.

a) ĐS: 2.4.

b) ĐS: 28.

c) HD: Đổi 12,1.360 thành 121.36. ĐS: 66

d) ĐS: 18.

a) \(\sqrt{0,09.64}\)

\(=\sqrt{0,09}.\sqrt{64}\)

\(=0,3.8=2,4\)

b) \(\sqrt{2^4.\left(-7\right)^2}\)

\(=\sqrt{2^4}.\sqrt{\left(-7\right)^2}\)

\(=2^2.7=4.7=28\)

c) \(\sqrt{12,1.360}\)

\(=\sqrt{121.36}\)

\(=\sqrt{121}.\sqrt{36}\)

\(=11.6=66\)

d) \(\sqrt{2^2.3^4}\)

\(=\sqrt{2^2}.\sqrt{3^4}\)

\(=2.3^2=2.9=18\)

a) đáp án :24

b) đáp án :28

c)đáp án :66

d)đáp án:18

a) \(\sqrt{0,09.64}=\sqrt{\left(0,3\right)^2.8^2}=0,3.8=2,4\)

b) \(\sqrt{2^4.\left(-7\right)^2}=\sqrt{\left(2^2\right)^2.\left(-7\right)^2}=2^2.\left|-7\right|=7.4=28\)

c) \(\sqrt{12,1.360}=\sqrt{12,1.10.36}=\sqrt{121.36}=\sqrt{11^2.6^2}=11.6=66\)

d) \(\sqrt{2^2.3^4}=\sqrt{2^2.\left(3^2\right)^2}=2.3^2=9.2=18\)

a) \(\sqrt{0,09\cdot64}=\sqrt{0,09}\cdot\sqrt{64}=0,3\cdot8=2,4\)

b) \(\sqrt{2^4\cdot\left(-7\right)^2}=\sqrt{2^4}\cdot\sqrt{\left(-7\right)^2}=2^2\cdot7=4\cdot7=28\)

c) \(\sqrt{12,1\cdot360}=\sqrt{12,1\cdot10\cdot36}=\sqrt{121\cdot36}=\sqrt{121}\cdot\sqrt{36}=11\cdot6=66\)

d) \(\sqrt{2^2\cdot3^4}=\sqrt{2^2}\cdot\sqrt{3^4}=2\cdot3^2=2\cdot9=18\)

= 66

75 . 48 = 25 . 3 . 3 . 16 = 25 . 3 2 . 16 = 5 . 3 . 4 = 60

90 . 6 , 4 = 9 . 64 = 9 . 64 = 3 . 8 = 24

45 . 80 = 9 . 5 . 5 . 16 = 9 . 5 2 . 16 = 3 . 5 . 4 = 60