几道二次根式的题目!1.2√2-4√1/27+3√482.(√3-√2)(-√3-√2)3.已知a=2+√5,b=2-√5,求√a^2-ab+b^2的值已知m为实数,化简:-√-m^3 - m√-1/m
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几道二次根式的题目!1.2√2-4√1/27+3√482.(√3-√2)(-√3-√2)3.已知a=2+√5,b=2-√5,求√a^2-ab+b^2的值已知m为实数,化简:-√-m^3 - m√-1/m
几道二次根式的题目!
1.2√2-4√1/27+3√48
2.(√3-√2)(-√3-√2)
3.已知a=2+√5,b=2-√5,求√a^2-ab+b^2的值
已知m为实数,化简:-√-m^3 - m√-1/m
几道二次根式的题目!1.2√2-4√1/27+3√482.(√3-√2)(-√3-√2)3.已知a=2+√5,b=2-√5,求√a^2-ab+b^2的值已知m为实数,化简:-√-m^3 - m√-1/m
1.2√2-4√1/27+3√48=2√2-4√3/9+12√3=2√2+104√3/9
2.(√3-√2)(-√3-√2)=(-√2)²-(√3)²=2-3=-1
3.已知a=2+√5,b=2-√5,
√a^2-ab+b^2=√(9+4√5)-(4-5)+(9-4√5)=√19
1. 2√2-4√1/27+3√48=2√2-4√3/3+12√3=2√2+32√3/3
2. (√3-√2)(-√3-√2)
=2-3=-1
3. 已知a=2+√5,b=2-√5,求√a^2-ab+b^2的值
√a^2-ab+b^2=√[4+4√5+5+1+4-4√5+5]=√19求补充问题答案-√-m^3 - m√-1/m...
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1. 2√2-4√1/27+3√48=2√2-4√3/3+12√3=2√2+32√3/3
2. (√3-√2)(-√3-√2)
=2-3=-1
3. 已知a=2+√5,b=2-√5,求√a^2-ab+b^2的值
√a^2-ab+b^2=√[4+4√5+5+1+4-4√5+5]=√19
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1. 2√2-4√1/27+3√48
=2√2-4/9√3+12√3
=2√2-(104√3)/9
2. (√3-√2)(-√3-√2)
=-3+2
=-1
3. 已知a=2+√5,b=2-√5,求√a^2-ab+b^2的值
√a^2-ab+b^2<...
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1. 2√2-4√1/27+3√48
=2√2-4/9√3+12√3
=2√2-(104√3)/9
2. (√3-√2)(-√3-√2)
=-3+2
=-1
3. 已知a=2+√5,b=2-√5,求√a^2-ab+b^2的值
√a^2-ab+b^2
=√(a²-2ab+b²+ab)
=√[(a-b)²+ab]
=√[(2+√5-2+√5)²+(2+√5)(2-√5)]
=√(5+4-5)
=√4
=2
已知m为实数,化简:-√-m^3 - m√-1/m
-√-m^3 - m√-1/m
=-√(-m)³-m√(-1/m)
=-(-m)√m-m/(-m)√m
=m√m-√m
=(m-1)√m
楼上错了两题
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