ĐKXĐ: x>0
\(E=4\sqrt{\dfrac{25x}{4}}-\dfrac{8}{3}\cdot\sqrt{\dfrac{9x}{4}}-\dfrac{4}{3x}\cdot\sqrt{\dfrac{9x^3}{64}}\)
\(=4\cdot\dfrac{5\sqrt{x}}{2}-\dfrac{8}{3}\cdot\dfrac{3\sqrt{x}}{2}-\dfrac{4}{3x}\cdot3x\cdot\dfrac{\sqrt{x}}{8}\)
\(=10\sqrt{x}-4\sqrt{x}-\dfrac{4\sqrt{x}}{8}=6\sqrt{x}-\dfrac{1}{2}\sqrt{x}=\dfrac{11}{2}\sqrt{x}\)
ĐKXĐ: a>0
\(D=a\sqrt{\dfrac{1}{a}}-\sqrt{25a}+18\sqrt{\dfrac{a}{9}}+\sqrt{\left(1+\sqrt{a}\right)^2}\)
\(=\dfrac{a}{\sqrt{a}}-5\sqrt{a}+\dfrac{18\sqrt{a}}{3}+\sqrt{a}+1\)
\(=\sqrt{a}-5\sqrt{a}+6\sqrt{a}+\sqrt{a}+1=3\sqrt{a}+1\)
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