\(a)\) \(A=\sqrt{49}-2\sqrt{36}+3\sqrt{4}\)
\(A=7-2.6+3.2\)
\(A=7-12+6\)
\(A=1\)
\(b)\) \(B=\frac{1}{2}\sqrt{\frac{144}{225}}-7\sqrt{100}+4\sqrt{\frac{361}{400}}\)
\(B=\frac{1}{2}.\frac{4}{5}-7.10+4.\frac{19}{20}\)
\(B=\frac{2}{5}-70+\frac{19}{5}\)
\(B=\frac{-329}{5}\)
Chúc bạn học tốt ~