\(\sqrt{23+8\sqrt{7}}-\sqrt{7}=\sqrt{4^2+2.4.\sqrt{7}+\left(\sqrt{7}\right)^2}-\sqrt{7}=\sqrt{\left(4+\sqrt{7}\right)^2}-\sqrt{7}=4+\sqrt{7}-\sqrt{7}=4\)
\(\sqrt{23+8\sqrt{7}}-\sqrt{7}=\sqrt{4^2+2.4.\sqrt{7}+\left(\sqrt{7}\right)^2}-\sqrt{7}=\sqrt{\left(4+\sqrt{7}\right)^2}-\sqrt{7}=4+\sqrt{7}-\sqrt{7}=4\)
Bài 1: rút gọn biểu thức
d)\(\sqrt{23+8\sqrt{7}}-\sqrt{7}\)
a)\(\sqrt{9-4\sqrt{5}}+\sqrt{5}\)
b)\(\sqrt{6-4\sqrt{2}}+\sqrt{2}\)
c)\(\sqrt{23+8\sqrt{7}}-\sqrt{7}\)
\(\sqrt{3-2\sqrt{2}}-\sqrt{11+6\sqrt{2}}\)
\(\sqrt{4-2\sqrt{3}}-\sqrt{7-4\sqrt{3}}+\sqrt{19+8\sqrt{3}}\)
\(\sqrt{6-2\sqrt{5}}+\sqrt{9+4\sqrt{5}}-\sqrt{14-6\sqrt{5}}\)
\(\sqrt{11-4\sqrt{7}}+\sqrt{23-8\sqrt{7}}+\sqrt{\left(-2^6\right)}\)
rút gọn:giải chi tiết hộ mình nha
Rút gọn biểu thức:
\(A=\sqrt{\left(\sqrt{7}-2\right)^2}+\sqrt{\left(\sqrt{7}-5\right)^2}\)
\(B=\sqrt{23+8\sqrt{7}}-\sqrt{7}\)
\(C=\sqrt{11+2\sqrt{30}}-\sqrt{11-2\sqrt{30}}\)
Đưa bth sau về dạng bình phương của 1 số thực:
a, \(9+4\sqrt{5}\)
b, \(23-8\sqrt{7}\)
c, \(4-2\sqrt{3}\)
d, \(11+6\sqrt{2}\)
Tính:
a) \(\left(2\sqrt{5}-\sqrt{7}\right).\left(2\sqrt{5}+\sqrt{7}\right)\)
b)\(\left(\sqrt{5-2\sqrt{6}}+\sqrt{2}\right).\sqrt{3}\)
c)\(\sqrt{7-4\sqrt{3}}+\sqrt{7+4\sqrt{3}}\)
d)\(\sqrt{15-6\sqrt{6}}+\sqrt{33-12\sqrt{6}}\)
e)\(\sqrt{3+\sqrt{5}}+\sqrt{3-\sqrt{5}}\)
g)\(\sqrt{8-2\sqrt{15}}-\sqrt{23-4\sqrt{15}}\)
\(\left(\sqrt{28}-2\sqrt{14}+\sqrt{7}\right).\sqrt{7}+7\sqrt{8}\)
tính:giải chi tiết nha
\(\sqrt{29-4\sqrt{7}}\)
\(\sqrt{19+6\sqrt{2}}\)
\(\sqrt{28-6\sqrt{3}}\)
\(\sqrt{46-6\sqrt{5}}\)
\(\sqrt{49+8\sqrt{3}}\)
\(\sqrt{32-8\sqrt{7}}\)
Tính giá trị các biểu thức:
A = \(\sqrt{8+2\sqrt{7}}-\sqrt{8-2\sqrt{7}}\)
B = \(\sqrt{11-6\sqrt{2}}+\sqrt{6-4\sqrt{2}}\)
rút gọn
\(\left(\sqrt{28}-2\sqrt{14}+\sqrt{7}\right).\sqrt{7}+7\sqrt{8}\)
giúp mink vs ạ