\(\left(\frac{\sqrt{x}+\sqrt{y}}{2\sqrt{x}-2\sqrt{y}}-\frac{2\sqrt{xy}}{x-y}\right).\frac{2\sqrt{x}}{\sqrt{x}-\sqrt{y}}\)
RÚT GỌN
Tính:
a) \(\frac{-90}{189}+\frac{45}{84}-\frac{78}{126}\)
b) \(11\frac{7}{21}+8\frac{16}{24}-10\frac{21}{35}\)
c) \(\frac{37}{43}\cdot\frac{17}{29}-\frac{21}{41}\cdot\frac{1}{2}+\frac{9}{58}:1\frac{6}{37}-\frac{6}{2}:1\frac{29}{21}\)
d) \(\sqrt{\left(-5\right)^2}+\sqrt{5^2}-\sqrt{\left(-5\right)^2}-\sqrt{3^2}\)
1) 7520 và 4510.530
2) \(\sqrt{40+2}và\sqrt{40}+\sqrt{2}\)
so sánh
\(\frac{x}{3}=\frac{y}{4}vàxy=12\)
tìm x;y
Mai tui nộp bài này r, TL hết nha pls
a)\(\sqrt{x=2}\)
b)\(\sqrt{\frac{x}{2}}=3\)
c)\(\sqrt{\frac{x}{2}}=\sqrt{\frac{y}{3}}\)và \(\sqrt{x}-\sqrt{y}=-1\)
d)\(\sqrt{\frac{x-3}{3}}=\sqrt{\frac{y-1-2}{4}}\)và \(\sqrt{x}=\sqrt{y-1}\)
1. Chứng minh:\(\left(\frac{x\sqrt{x}+27y\sqrt{y}}{3\sqrt{x}+9\sqrt{y}}-\sqrt{xy}\right).\left(\frac{3\sqrt{x}+9\sqrt{y}}{9y-x}\right)^2>\sqrt{8}\)
2. Rút gọn A= \(\frac{\sqrt{a+2\sqrt{a-1}}+\sqrt{a-2\sqrt{a-1}}}{\sqrt{a+\sqrt{2a-1}}-\sqrt{a-\sqrt{2a-1}}}\)
SO SÁNH 45 VỚI S
\(S=\frac{1}{\sqrt{1}}+\frac{1}{\sqrt{2}-\sqrt{1}}+\frac{1}{\sqrt{3}-\sqrt{2}}+...+\frac{1}{\sqrt{2025}-\sqrt{2024}}\)
So sánh các số x và y, nếu
a)\(x=\sqrt{961}-\left(\frac{1}{\sqrt{6}}-1\right)\)và \(y=\sqrt{1089}-\left(\frac{1}{\sqrt{7}}+1\right)\)
b) \(\sqrt{0,01}+\sqrt{0,04}+\sqrt{0,09}+\sqrt{0,16}+...+\sqrt{0,81}\)và \(y=\sqrt{20+0,25}\)
c) \(x=\left(1-\frac{1}{\sqrt{4}}\right).\left(1-\frac{1}{\sqrt{16}}\right).\left(1-\frac{1}{\sqrt{36}}\right).\left(1-\frac{1}{\sqrt{64}}\right).\left(1-\frac{1}{\sqrt{100}}\right)\)và\(y=\sqrt{0,1}\)
a,
\(x=3\sqrt{2
}\)
\(y=2\sqrt{3}\)
b,
\(x=\sqrt{3}+\sqrt{6}\)
\(y=\sqrt{2}+\sqrt{7}\)
c,
\(x=-\frac{1}{2}\sqrt{\frac{1}{3}}\)
\(y=-\frac{1}{3}\sqrt{-\frac{1}{2}}\)
b1: rút gọn biểu thức:
\(A=\frac{1-\frac{1}{\sqrt{49}}+\frac{1}{49}-\frac{1}{\left(7.\sqrt{7}\right)^2}}{\frac{\sqrt{64}}{2}-\frac{4}{7}+\left(\frac{2}{7}\right)^2-\frac{4}{343}}\)
b2: tìm x, y, z thỏa mãn:
\(\sqrt{\left(x-\sqrt{2}\right)^2}_{ }\)+ \(\sqrt{\left(y+\sqrt{2}\right)^2}^{ }\)+ |x+y+z| = 0
nhanh nhé, ai đúng mk t*** cho !!!