ĐKXĐ: x>=1
\(2\sqrt{x-1}=\sqrt{25}-\sqrt{\dfrac{1}{4}}\)
=>\(2\sqrt{x-1}=5-\dfrac{1}{2}=\dfrac{9}{2}\)
=>\(\sqrt{x-1}=\dfrac{9}{4}\)
=>\(x-1=\left(\dfrac{9}{4}\right)^2=\dfrac{81}{16}\)
=>\(x=\dfrac{81}{16}+1=\dfrac{97}{16}\left(nhận\right)\)
a)22+2x+3=144
b)(\(\sqrt{9}+\sqrt{4}\)).\(\sqrt{x}\)=10
c)(x+\(\dfrac{1}{2}\))2=\(\dfrac{4}{25}\)
tính
A) \(\sqrt{121}-\sqrt{\dfrac{1}{4}}+\sqrt{\dfrac{25}{36}}\)
b) \(\dfrac{3}{4}.\dfrac{-5}{7}-\dfrac{3}{4}.\dfrac{2}{7}\)
a) \(\sqrt{\left(-7\right)^2}+\sqrt{\dfrac{25}{16}}-\dfrac{3}{2}\) b) \(23\dfrac{1}{3}.\dfrac{-1}{4}-13\dfrac{1}{3}.\dfrac{-1}{4}\)
a) \(4.\left(-\dfrac{1}{2}\right)^3\)\(-2.\left(-\dfrac{1}{2}\right)^2\)+\(3.\left(-\dfrac{1}{2}\right)\)+1
b) \(8.\sqrt{9}\)\(-\sqrt{64}\)
c) \(\sqrt{\dfrac{9}{16}}\)\(+\dfrac{25}{46}\)\(:\dfrac{5}{23}\)\(-\dfrac{7}{4}\)
đung cho 5 sao
giúp mình với
1, tính
a, \(7\times\sqrt{\dfrac{6^2}{7^2}}-\sqrt{25}+\sqrt{\dfrac{\left(-3\right)^2}{2}}\)
b, \(-\sqrt{\dfrac{64}{49}}-\dfrac{3}{5}\times\sqrt{\dfrac{25}{64}}+\sqrt{0,25}\)
c, \(\sqrt{\dfrac{10000}{5}}-\dfrac{1}{4}.\sqrt{\dfrac{16}{9}}+\sqrt{\dfrac{\left(-3\right)^2}{\left(4\right)}}\)
d, \(\left|\dfrac{1}{4}-\sqrt{0,0144}\right|-\dfrac{3}{2}+\sqrt{\dfrac{81}{169}}\)
Thực hiện pháp tính :
25.(\(\dfrac{-1}{5}\)) + \(\dfrac{1}{5}\) - 2 . (\(\dfrac{-1}{2}\))\(^2\) - \(\sqrt{\dfrac{1}{4}}\)
Tìm x :
6 - | \(\dfrac{1}{2}\) - x | = \(\dfrac{2}{5}\)
a/ 5 .\(\sqrt{0,01}\) - \(\sqrt{0,25}\)
b/ 15\(\dfrac{1}{4}\) : (-\(\dfrac{5}{7}\)) - 25\(\dfrac{1}{4}\) : (-\(\dfrac{5}{7}\))
c/ \(\dfrac{5^4\cdot20^4}{25^4\cdot4^5}\)
\(\sqrt{\dfrac{4}{81}}:\sqrt{\dfrac{25}{81}}-1\dfrac{3}{5}\)
a,-12:(3/4-5/6)^2
,b,10.\(\sqrt{0.01}.\sqrt{\dfrac{16}{9}+3\sqrt{49}-\dfrac{1}{6}\sqrt{4}}\)
c,x/6=y/3=z/2 và x-2y+4z=8
d,|1/4+x|-1/3=2/5
Bài 1: Tìm x; y ϵ \(ℤ\)
a) 2x - y\(\sqrt{6}\) = 5 + (x + 1)\(\sqrt{6}\)
b) 5x + y - (2x -1)\(\sqrt{7}\) = y\(\sqrt{7}\) + 2
Bài 2: So sánh M và N
M = \(\dfrac{\dfrac{3}{4}+\dfrac{3}{5}+\dfrac{3}{7}-\dfrac{3}{11}}{\dfrac{6}{4}+\dfrac{6}{5}+\dfrac{6}{7}-\dfrac{6}{11}}\)
N = \(\dfrac{\dfrac{2}{3}+\dfrac{2}{5}-\dfrac{2}{7}-\dfrac{2}{11}}{\dfrac{6}{2}+\dfrac{6}{5}-\dfrac{6}{7}-\dfrac{6}{11}}\)
Bài 3: Chứng minh:
\(\dfrac{1}{2!}+\dfrac{1}{3!}+\dfrac{1}{4!}+...+\dfrac{1}{2023!}< 1\)
