\(\frac{x^2}{3969}=\sqrt{123-10^2}\)
\(\frac{x^2}{3969}=\sqrt{125-100}\)
\(\frac{x^2}{3969}=\sqrt{25}\)
\(\frac{x^2}{3696}=5\)
\(\Rightarrow\) \(x^2=5\times3696\)
Đến đây thì bn tự làm nha
Tính:
a) \(\sqrt{125}+\sqrt{\left(-14\right)^2}-\sqrt{225}\)
b) \(\sqrt{\frac{9}{49}}.\sqrt{\left(\frac{-1}{3}\right)^2}+\sqrt{\frac{4}{9}}\)
Tim x
\(\frac{x-5}{5x-1}=\frac{y}{3}=\frac{4x-10}{20x+4}\)
\(\frac{5}{y}=\frac{3}{x}\)và y mũ 2 + x mũ 2 = 125
Tính giá trị của biểu thức:
a) \(\sqrt{49}+\sqrt{\left(-5\right)^2}-5\sqrt{1,44}+3\sqrt{\frac{4}{9}}\)
b) \(\left(2\sqrt{3}\right)^2-\left(3\sqrt{2}\right)^2+\left(4.\sqrt{0,5}\right)^2-\left(\frac{1}{5}.\sqrt{125}\right)^2\)
Tìm x biết:
a) \(\frac{1}{4}+\frac{1}{3}:2x=-5\)
b) \(\left(3x-\frac{1}{4}\right).\left(x+\frac{1}{2}\right)=0\)
c) \(|x+\frac{1}{5}|-\frac{1}{2}=\frac{9}{10}\)
d) \(\sqrt{0,81}.\left(\sqrt{x}+\sqrt{\frac{16}{49}}\right)=\frac{9}{10}\)
f) \(|\frac{1}{3}.\sqrt{x+1}-\frac{2}{9}|-\frac{1}{6}=\frac{1}{9}\)
Tìm x biết
\(\sqrt{1,69}\left(2\sqrt{x}+\sqrt{\frac{81}{21}}\right)=\frac{13}{10}\)
\(y=\frac{10\sqrt[2]{3}}{x^2+\sqrt{x}}\)
Tìm x biết \(\frac{x+2}{327}+\frac{x+3}{326}+\frac{x+4}{325}+\frac{x+5}{324}+\frac{x+349}{5}=0\)
CMR:\(\frac{1}{2!}+\frac{2}{3!}+\frac{3}{4!}+...+\frac{99}{100!}< 1\)
\(\frac{1}{\sqrt{1}}+\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{3}}+...+\frac{1}{\sqrt{100}}>10\)
Tính \(B=1+\frac{1}{2}\left(1+2\right)+\frac{1}{3}\left(1+2+3\right)+\frac{1}{4}\left(1+2+3+4\right)+...+\frac{1}{20}\left(1+2+3+...+20\right)\)
Tìm x biết
1, \(\sqrt{0.81}.\left(\sqrt{x}+\sqrt{\frac{16}{44}}\right)=\frac{9}{10}\)
2, / \(\frac{1}{3}.\sqrt{x+1}-\frac{2}{9}\)/ -\(\frac{1}{6}=\frac{1}{9}\)
Tính Nhanh:\(\frac{\left(\frac{1}{10}-\frac{\sqrt{2}}{7}+\frac{3\sqrt{2}}{35}\right).\left(-\frac{4}{15}\right)}{\left(\frac{1}{10}+\frac{3\sqrt{2}}{25}-\frac{\sqrt{2}}{5}\right).\frac{5}{7}}\)
