Question

Answer 1

bạn nên tách ra từng bài để dễ trả lời hơn 

Answer 2

bài 1
\(\sqrt{36}=6\)
\(\sqrt{81}=9\)
\(\sqrt{49}=7\)
\(\sqrt{225}=15\)
\(\sqrt{0,0144}=\sqrt{\dfrac{144}{10000}}=\sqrt{\dfrac{12}{100}}=\sqrt{\dfrac{3}{25}}=\dfrac{\sqrt{3}}{5}\)

Answer 3

B1

\(\sqrt{81}=9.vì.9>0.và.9^2=81\)

\(\sqrt{49}=7.vì.7>0.và.7^2=49\)

\(\sqrt{225}=15.vì15>0.và.15^2=225\)

\(\sqrt{0,0144}=\dfrac{3}{25}.vì.\dfrac{3}{25}>0.và\left(\dfrac{3}{25}\right)^2=0,0144\)

Answer 4

bài 2
a.
\(\dfrac{\sqrt{27}}{\sqrt{3}}=\sqrt{\dfrac{27}{3}}=\sqrt{9}=3\)
b.
\(\dfrac{\sqrt{25}}{\sqrt{121}}=\dfrac{5}{11}\)
c.
\(\sqrt{3}.\sqrt{27}=\sqrt{3.27}=\sqrt{81}=9\)
d.
\(\sqrt{25.49}=\sqrt{25}.\sqrt{49}=5.7=35\)

Answer 5

bài 3
a. \(3\sqrt{16}-2\sqrt{9}+\dfrac{\sqrt{8}}{\sqrt{2}} =3.4-2.3+2=8\)
b.\(\sqrt{64}+4\sqrt{4}+2000=8+8+2000=2016\)

Answer 6

\(\sqrt{18}-\sqrt{50}=\sqrt{2.9}-\sqrt{25.2}=3\sqrt{2}-5\sqrt{2}=-2\sqrt{2}\)
\(\sqrt{2}+\sqrt{18}=\sqrt{2}+3\sqrt{2}=4\sqrt{2}\)
\(\sqrt{45}-2\sqrt{20}=\sqrt{9.5}-2\sqrt{4.5}=3\sqrt{5}-4\sqrt{5}=-\sqrt{5}\)
\(\sqrt{27}-\sqrt{12}=\sqrt{9.3}-\sqrt{3.4}=3\sqrt{3}-2\sqrt{3}=\sqrt{3}\)

Answer 7

\(3\sqrt{44}-2\sqrt{99}=3\sqrt{4.11}-2\sqrt{9.11}=6\sqrt{11}-6\sqrt{11}=0\)
\(\sqrt{72}-\sqrt{8}=\sqrt{9.8}-\sqrt{8}=3\sqrt{8}-\sqrt{8}=2\sqrt{8=4\sqrt{2}}\)
\(2\sqrt{8}-5\sqrt{18}+4\sqrt{32}=4\sqrt{2}-15\sqrt{2}+16\sqrt{2}=5\sqrt{2}\)
\(\sqrt{45}+\sqrt{20}-\sqrt{5}=3\sqrt{5}+2\sqrt{5}-\sqrt{5}=4\sqrt{5}\)
\(\sqrt{8}-\sqrt{32}+\sqrt{50}=2\sqrt{2}-4\sqrt{2}+5\sqrt{2=3\sqrt{2}}\)
\(\sqrt{12}+\sqrt{27}-4\sqrt{3}=2\sqrt{3}+3\sqrt{3}-4\sqrt{3}=\sqrt{3}\)