d: ĐKXĐ: \(x>=-\dfrac{1}{5}\)
\(\sqrt{25x+5}+\sqrt{45}\cdot\sqrt{20x+4}-\sqrt{\dfrac{5x+1}{16}}=\dfrac{28\sqrt{5}-1}{4}\)
=>\(\sqrt{5}\cdot\sqrt{5x+1}+3\sqrt{5}\cdot2\sqrt{5x+1}-\dfrac{\sqrt{5x+1}}{4}=\dfrac{28\sqrt{5}-1}{4}\)
=>\(\sqrt{5x+1}\left(\sqrt{5}+6\sqrt{5}-\dfrac{1}{4}\right)=\dfrac{28\sqrt{5}-1}{4}\)
=>\(\sqrt{5x+1}\cdot\dfrac{-1+28\sqrt{5}}{4}=\dfrac{28\sqrt{5}-1}{4}\)
=>\(\sqrt{5x+1}=1\)
=>\(5x+1=1\)
=>5x=0
=>x=0(nhận)
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