=>\(25\cdot\dfrac{\sqrt{a-3}}{5}-7\cdot\dfrac{2}{3}\cdot\sqrt{a-3}-7\sqrt{a^2-9}+18\cdot\dfrac{1}{3}\sqrt{a^2-9}=0\)
=>\(\sqrt{a-3}\cdot\dfrac{1}{3}-\sqrt{a^2-9}=0\)
=>\(\sqrt{a-3}\left(\dfrac{1}{3}-\sqrt{a+3}\right)=0\)
=>a-3=0 hoặc a+3=1/9
=>a=3 hoặc a=-26/9
\(25\sqrt{\dfrac{x-3}{25}}-7\sqrt{\dfrac{4x-12}{9}}-7\sqrt{x^2-9}+18\sqrt{\dfrac{9x^2-81}{81}}=0\)
Giải phương trình.
giúp e với ạaa :< gấp aa :((
Giải các phương trình sau
a) \(25\sqrt{\frac{a-3}{25}}-7\sqrt{\frac{4a-12}{9}}-7\sqrt{a^2-9}+18\sqrt{\frac{9a^2-81}{81}}=0\)
b)\(\sqrt{18x+9}-\sqrt{8x+4}+\frac{1}{3}\sqrt{2x+1}=4\)
Giải phương trình : \(25\sqrt{\frac{a-3}{25}}\)--- \(7\sqrt{\frac{4a-12}{9}}\)--- \(7\sqrt{a^2-9}\)+ \(18\sqrt{\frac{9a^2-81}{81}}\)= 0
a) \(\sqrt{4x^2-9}=2\sqrt{x+3}\)
b) \(\sqrt{4x+20}+3\sqrt{\dfrac{x-5}{9}}-\dfrac{1}{3}\sqrt{9x-45}=4\)
c) \(\dfrac{2}{3}\sqrt{9x-9}-\dfrac{1}{4}\sqrt{16x-16}+27\sqrt{\dfrac{x-1}{81}}=4\)
d)\(5\sqrt{\dfrac{9x-27}{25}}-7\sqrt{\dfrac{4x-12}{9}}-7\sqrt{x^2-9}+18\sqrt{\dfrac{9x^2-81}{81}}=0\)
a \(\sqrt{4x-20}+\sqrt{x-5}-\dfrac{1}{3}\sqrt{9x-45}=4\)
b \(\sqrt{x-1}+\sqrt{4x-4}-\sqrt{25x-25}=4\)
c \(\dfrac{1}{3}\sqrt{x-2}-\dfrac{2}{3}\sqrt{9x-18}+6\sqrt{\dfrac{x-2}{81}=-4}\)
d \(\sqrt{9x+27}+4\sqrt{x+3}-\dfrac{3}{4}\sqrt{16x+48}=0\)
a) \(\dfrac{2}{5}\sqrt{25}\) -\(\dfrac{1}{2}\sqrt{4}\) b)0,5\(\sqrt{0,09}\) +5\(\sqrt{0,81}\) c)\(\dfrac{2}{5}\sqrt{\dfrac{25}{36}}\) -\(\dfrac{5}{2}\sqrt{\dfrac{4}{25}}\)
d)-2\(\sqrt{\dfrac{-36}{-16}}\) + 5\(\sqrt{\dfrac{-81}{-25}}\)
cho x=\(\left(\dfrac{\sqrt[3]{8-3\sqrt{5}}+\sqrt[3]{64-12\sqrt{20}}}{\sqrt[3]{57}}\right)\sqrt[3]{8+3\sqrt{5}}\);y=\(\left(\dfrac{\sqrt[3]{9}-\sqrt{2}}{\sqrt[3]{3}+\sqrt[4]{2}}+\dfrac{\sqrt{2}-9\sqrt[3]{9}}{\sqrt[4]{2}-\sqrt[3]{81}}\right)\)
a rút gọn x và y
b tính T = xy
Giải phương trình: \(5\sqrt{\frac{9x-27}{25}}-7\sqrt{\frac{4x-12}{9}}-7\sqrt{x^2-9}+18\sqrt{\frac{9x^2-81}{91}}=0\)
a : \(\dfrac{\sqrt{x}}{\sqrt{x}+3}+\dfrac{2\sqrt{x}}{\sqrt{x}-3}-\dfrac{3x+9}{x-9}\)với x ≥ 0 x ≠ 9
b : \(\dfrac{3}{\sqrt{x}-1}-\dfrac{\sqrt{x}+5}{x-1}\)với x ≥ 0 x ≠ 1
c : \(\left(\dfrac{15-\sqrt{x}}{x-25}+\dfrac{2}{\sqrt{x}+5}\right):\dfrac{\sqrt{x}+1}{\sqrt{x}-5}\)với x ≥ 0 x ≠ 0
d : \(\dfrac{3\sqrt{x}+1}{x+2\sqrt{x}-3}-\dfrac{2}{\sqrt{x}+3}\)với x ≥ 0 x ≠ 1
