Bài 8: Rút gọn biểu thức chứa căn bậc hai
Các câu hỏi tương tự
Rút gọn các biểu thức sau :
a) \(\left(1+\dfrac{3-\sqrt{3}}{\sqrt{3}-1}\right)\left(\dfrac{3+\sqrt{3}}{\sqrt{3}+1}-1\right)\)
b) \(\left(\dfrac{\sqrt{6}-\sqrt{2}}{1-\sqrt{3}}-\dfrac{5}{\sqrt{5}}\right):\:\dfrac{1}{\sqrt{5}-\sqrt{2}}\)
c) \(\dfrac{7-4\sqrt{3}}{\sqrt{3}-2}-\dfrac{28-10\sqrt{3}}{5-\sqrt{3}}\)
tính:
\(\left(\dfrac{3\sqrt{5}-\sqrt{2}}{\sqrt{5}+\sqrt{2}}-\dfrac{\sqrt{5}+\sqrt{2}}{\sqrt{5}-\sqrt{2}}\right).\dfrac{\sqrt{5}-3}{5-3\sqrt{10}}\)
\(5\left(\sqrt{2+\sqrt{3}}+\sqrt{3-\sqrt{5}}-\sqrt{\dfrac{5}{2}}\right)^2+\left(\sqrt{2-\sqrt{3}}+\sqrt{3+\sqrt{5}}-\sqrt{\dfrac{3}{2}}\right)^2\)
Rút gọn:
1) \(\dfrac{16-6\sqrt{7}}{\sqrt{7}-3}\)
2) \(\dfrac{\left(\sqrt{3}-\sqrt{2}\right)^2+4\sqrt{6}}{\sqrt{3}+\sqrt{2}}\)
3) \(\dfrac{\left(\sqrt{3}+2\sqrt{5}\right)^2-8\sqrt{15}}{\sqrt{6}-2\sqrt{10}}\)
Giúp em với ạ. Help mee !!!
tính1.left(sqrt{15}-2sqrt{3}right)^2+12sqrt{5}2.3sqrt{2}left(4-sqrt{2}right)+3left(1-2sqrt{2}right)^23.dfrac{1}{2}left(sqrt{6}+sqrt{5}right)^2-dfrac{1}{4}sqrt{120}-sqrt{dfrac{15}{2}}4.left(sqrt{4-sqrt{7}}-sqrt{4+sqrt{7}}right)^25.left(sqrt{sqrt{14}+sqrt{5}}+sqrt{sqrt{14}-sqrt{5}}right)^26.left(sqrt{3}+1right)^3-left(sqrt{3}-1right)^37.left(sqrt{2}+1right)^3-left(sqrt{2}-1right)^38.sqrt{13-sqrt{160}}-sqrt{53+4sqrt{90}}9.sqrt{3-sqrt{5}}+sqrt{3+sqrt{5}}
Đọc tiếp
tính
1.\(\left(\sqrt{15}-2\sqrt{3}\right)^2+12\sqrt{5}\)
2.\(3\sqrt{2}\left(4-\sqrt{2}\right)+3\left(1-2\sqrt{2}\right)^2\)
3.\(\dfrac{1}{2}\left(\sqrt{6}+\sqrt{5}\right)^2-\dfrac{1}{4}\sqrt{120}-\sqrt{\dfrac{15}{2}}\)
4.\(\left(\sqrt{4-\sqrt{7}}-\sqrt{4+\sqrt{7}}\right)^2\)
5.\(\left(\sqrt{\sqrt{14}+\sqrt{5}}+\sqrt{\sqrt{14}-\sqrt{5}}\right)^2\)
6.\(\left(\sqrt{3}+1\right)^3-\left(\sqrt{3}-1\right)^3\)
7.\(\left(\sqrt{2}+1\right)^3-\left(\sqrt{2}-1\right)^3\)
8.\(\sqrt{13-\sqrt{160}}-\sqrt{53+4\sqrt{90}}\)
9.\(\sqrt{3-\sqrt{5}}+\sqrt{3+\sqrt{5}}\)
Làm mất căn mẫu và thu gọn
1) dfrac{sqrt{15}-sqrt{5}}{sqrt{3}-1}+dfrac{5-2sqrt{5}}{2sqrt{5}-4}
2) left(1-dfrac{5+sqrt{5}}{1+sqrt{5}}right)left(dfrac{5-sqrt{5}}{1-sqrt{5}}-1right)
3) left(dfrac{3sqrt{125}}{15}-dfrac{10-4sqrt{5}}{sqrt{5}-2}right)dfrac{1}{sqrt{5}}
4) dfrac{1}{1+sqrt{2}}-dfrac{1}{1-sqrt{2}}
5) dfrac{1}{3+sqrt{5}}-dfrac{1}{sqrt{5}-3}
6) dfrac{sqrt{3}+sqrt{2}}{sqrt{3}-sqrt{2}}+dfrac{sqrt{2}-sqrt{3}}{sqrt{2}+sqrt{3}}
7) dfrac{4}{1-sqrt{3}}+dfrac{sqrt{3}-1}{sqrt{3}+1}
8) dfrac{s...
Đọc tiếp
Làm mất căn mẫu và thu gọn
1) \(\dfrac{\sqrt{15}-\sqrt{5}}{\sqrt{3}-1}+\dfrac{5-2\sqrt{5}}{2\sqrt{5}-4}\)
2) \(\left(1-\dfrac{5+\sqrt{5}}{1+\sqrt{5}}\right)\left(\dfrac{5-\sqrt{5}}{1-\sqrt{5}}-1\right)\)
3) \(\left(\dfrac{3\sqrt{125}}{15}-\dfrac{10-4\sqrt{5}}{\sqrt{5}-2}\right)\dfrac{1}{\sqrt{5}}\)
4) \(\dfrac{1}{1+\sqrt{2}}-\dfrac{1}{1-\sqrt{2}}\)
5) \(\dfrac{1}{3+\sqrt{5}}-\dfrac{1}{\sqrt{5}-3}\)
6) \(\dfrac{\sqrt{3}+\sqrt{2}}{\sqrt{3}-\sqrt{2}}+\dfrac{\sqrt{2}-\sqrt{3}}{\sqrt{2}+\sqrt{3}}\)
7) \(\dfrac{4}{1-\sqrt{3}}+\dfrac{\sqrt{3}-1}{\sqrt{3}+1}\)
8) \(\dfrac{\sqrt{2}-1}{\sqrt{2}+1}-\dfrac{3}{\sqrt{2}-1}\)
9) \(\dfrac{\sqrt{2}}{\sqrt{\sqrt{2}+1}-1}-\dfrac{\sqrt{2}}{\sqrt{\sqrt{2}+1}+1}\)
10) \(\dfrac{\sqrt{15}-\sqrt{12}}{\sqrt{5}-2}-\dfrac{1}{2-\sqrt{3}}\)
11) \(\dfrac{5}{1+\sqrt{6}}-\dfrac{3\sqrt{2}-2\sqrt{3}}{\sqrt{3}-\sqrt{2}}\)
12) \(\dfrac{5}{3-\sqrt{7}}-\dfrac{3}{\sqrt{2}+\sqrt{3}}+\dfrac{-1}{\sqrt{2}-1}\)
Giúp em giải với ạ! Help me~!
tính giá trị biểu thức :
a, \(\left(\sqrt{28}+2\sqrt{14}+\sqrt{7}\right)\sqrt{7}-\left(7+\sqrt{2}\right)^2\)
b, \(\sqrt{\dfrac{5}{2}}+\dfrac{\sqrt{2}}{\sqrt{3}+\sqrt{5}}\)
c, \(\dfrac{8+2\sqrt{15}}{\sqrt{5}+\sqrt{3}}+\dfrac{7-2\sqrt{10}}{\sqrt{5}-\sqrt{2}}\)
d,\(\dfrac{3+4\sqrt{3}}{\sqrt{6}+\sqrt{2}-\sqrt{5}}\)
A=\(\sqrt{12-6\sqrt{3}}+\sqrt{21-12\sqrt{3}}\)
B=\(5\left(\sqrt{2+\sqrt{3}}+\sqrt{3-\sqrt{5}}-\sqrt{\dfrac{5}{2}}\right)^2+\left(\sqrt{2-\sqrt{3}}+\sqrt{3+\sqrt{5}}-\sqrt{\dfrac{3}{2}}\right)^2\)
thực hiện phép tính
a)\(\dfrac{\left(2+\sqrt{3}\right)\sqrt{2-\sqrt{3}}}{\sqrt{2+\sqrt{3}}}\)
b)\(\dfrac{\left(\sqrt{5}-1\right)^3}{\sqrt{5}-2}\)
c)\(\left(\sqrt{2}+1\right)^3-\left(\sqrt{2}-1\right)^3\)
d)\(\dfrac{\sqrt{3+\sqrt{5}}}{\sqrt{2}}-\dfrac{\sqrt{5}-1}{2}\)