Đáp án:
Giải thích các bước giải:
\(6)\ A=\sqrt{11-4\sqrt{7}}=\sqrt{7-2.\sqrt{7}.\sqrt{4}+4}=\sqrt{(\sqrt{7}+2)^{2}}=\sqrt{7}+2\\ 7)\ A=\sqrt{7-4\sqrt{3}}=\sqrt{3-2.\sqrt{4}.\sqrt{3}+4}=\sqrt{(3-\sqrt{2})^{2}}=3-\sqrt{2}\\ 8)\ A=\sqrt{12+6\sqrt{3}}=\sqrt{9+2.\sqrt{9}.\sqrt{3}+3}=\sqrt{(3+\sqrt{3})^{2}}=3+\sqrt{3}\\ 9)\ A=\sqrt{79+20\sqrt{3}}=\sqrt{75+2.\sqrt{75}.\sqrt{4}+4}=\sqrt{(\sqrt{75}+2)^{2}}=\sqrt{75}+2=5\sqrt{3}+2\\ 10)\ A=\sqrt{11+6\sqrt{2}}=\sqrt{9+2\sqrt{9}.\sqrt{2}+2}=\sqrt{(\sqrt{3}+2)^{2}}=\sqrt{3}+2\)
chúc bạn học tốt!
