\(\sqrt{10-2\sqrt{21}}+\sqrt{10+2\sqrt{21}}\)

\(=\sqrt{7-2\sqrt{21}+3}+\sqrt{7+2\sqrt{21}+3}\)

\(=\sqrt{\left(\sqrt{7}\right)^2-2.\sqrt{7}.\sqrt{3}+\left(\sqrt{3}\right)^2}+\sqrt{\left(\sqrt{7}\right)^2+2.\sqrt{7}.\sqrt{3}+\left(\sqrt{3}\right)^2}\)

\(=\sqrt{\left(\sqrt{7}-\sqrt{3}\right)^2}+\sqrt{\left(\sqrt{7}+\sqrt{3}\right)^2}\)

\(=\left|\sqrt{7}-\sqrt{3}\right|+\left|\sqrt{7}+\sqrt{3}\right|\)

\(=\sqrt{7}-\sqrt{3}+\sqrt{7}+\sqrt{3}\)

\(=\sqrt{7}+\sqrt{7}=2\sqrt{7}\)

Ta có: \(\sqrt{10-2\sqrt{21}}+\sqrt{10+2\sqrt{21}}\)

\(=\sqrt{7}-\sqrt{3}+\sqrt{7}+\sqrt{3}\)

\(=2\sqrt{7}\)

10/29+11/29+12/29+...+19/29

=10+11+12+13+14+15+=16+17+18+19/29

=145/29

\(=\sqrt{7-2\sqrt{21}+3}+\sqrt{7+2\sqrt{21}+3}\)

\(=\sqrt{\sqrt{7}^2-2\sqrt{7}.\sqrt{3}+\sqrt{3}^2}+\sqrt{\sqrt{7}^2+2\sqrt{7}.\sqrt{3}+\sqrt{3}^2}\)

\(=\sqrt{\left(\sqrt{7}-\sqrt{3}\right)^2}+\sqrt{\left(\sqrt{7}+\sqrt{3}\right)^2}\)

\(=\left|\sqrt{7}-\sqrt{3}\right|+\left|\sqrt{7}+\sqrt{3}\right|\)

\(=\sqrt{7}-\sqrt{3}+\sqrt{7}+\sqrt{3}\)

\(=2\sqrt{7}\)

\(\sqrt{10-2\sqrt{21}}+\sqrt{10+2\sqrt{21}}\)

\(=\sqrt{7}-\sqrt{3}+\sqrt{7}+\sqrt{3}\)

\(=2\sqrt{7}\)

có kết quả r mà

\(a\)) \(\left(4^2.4^3\right):2^{10}\)

   \(=4^5:2^{10}\)

   \(=\left(2^2\right)^5:2^{10}\)

   \(=2^{10}:2^{10}\)

   \(=1\)  

    \(b\)) \(\left(0,6\right)^5:\left(0,2\right)^6\)

    \(=\left(\frac{3}{5}\right)^5:\left(\frac{1}{5}\right)^6\)

     \(=\frac{3^5}{5^5}:\frac{1^6}{5^6}\)

      \(=\frac{3^5}{5^5}.5^6\)

        \(=\frac{3^5.5^6}{5^5}\)

        \(=3^5.5\)

         \(=243.5\)

          \(=1215\)

 \(c\)) \(\left(2^7.9^3\right):\left(6^5.8^2\right)\)

     \(=\left[2^7.\left(3^2\right)^3\right]:\left[\left(2.3\right)^5.\left(2^4\right)^2\right]\)

      \(=\left(2^7.3^6\right):\left[2^5.3^5.2^8\right]\)

       \(=\left(2^7.3^6\right).\left(\frac{1}{2^5.3^5.2^8}\right)\)

         \(=\frac{2^7.3^6.1}{\left(2^5.2^8\right).3^5}\)

           \(=\frac{2^7.3^6}{2^{13}.3^5}\)

           \(=\frac{3}{2^6}\)

           \(=\frac{3}{64}\)

3/8 + 1/2 = 7/8

9/8 - 1/6 = 23/24

a: =1/2(3/4+1)=1/2x7/4=7/8

b: =9/8-1/6=27/24-4/24=23/24

=(4x0.25)x(2x0.5)

=1x1=1

ủa ko biết nữa ko biết nữa ko biết đáp án ở đâu