tính nhanh!

T

tuananh8

Tính:
a) [TEX]\sqrt[3]{162}-\sqrt[3]{48}-\sqrt[3]{6}[/TEX]
b) [TEX]\sqrt[3]{1+\sqrt[]{2}}.\sqrt[6]{3-2\sqrt[]{2}}[/TEX]

a) [TEX]\sqrt[3]{162}-\sqrt[3]{48}-\sqrt[3]{6}=\sqrt[3]{27.6}-\sqrt[3]{8.6}-\sqrt[3]{6}=3\sqrt[3]{6}-2\sqrt[3]{6}-\sqrt[3]{6}=0[/TEX]



Tính:
b) [TEX]\sqrt[3]{1+\sqrt[]{2}}.\sqrt[6]{3-2\sqrt[]{2}}[/TEX]

b) [TEX]\sqrt[3]{1+\sqrt[]{2}}.\sqrt[6]{3-2\sqrt[]{2}} = (\sqrt[6]{(1+\sqrt 2)^2}) .( \sqrt[6]{3-2\sqrt 2}) = \sqrt[6]{3+2\sqrt 2}.\sqrt[6]{3-2\sqrt 2}[/TEX]

[TEX]= \sqrt[6]{(3+2\sqrt 2 )(3-2\sqrt 2)} = \sqrt[6]{9-4.2}=1[/TEX]
 
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T

tominhduc_06

a) [TEX]\sqrt[3]{162}-\sqrt[3]{48}-\sqrt[3]{6}=\sqrt[3]{27.6}-\sqrt[3]{8.6}-\sqrt[3]{6}=3\sqrt[3]{6}-2\sqrt[3]{6}-\sqrt[3]{6}=0[/TEX]





b) [TEX]\sqrt[3]{1+\sqrt[]{2}}.\sqrt[6]{3-2\sqrt[]{2}} = (\sqrt[6]{(1+\sqrt 2)^2}) .( \sqrt[6]{3-2\sqrt 2}) = \sqrt[6]{3+2\sqrt 2}.\sqrt[6]{3-2\sqrt 2}[/TEX]

[TEX]= \sqrt[6]{(3+2\sqrt 2 )(3-2\sqrt 2)} = \sqrt[6]{9-4.2}=1[/TEX]

Cảm ơn bạn nhìu nha ;))
 
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