Tính
2 . \(\frac{\sqrt{0,01}}{1,21}\)+ 3 . 2/ \(\sqrt{100}+4+40\)- 3/4
tính :
\(B=2\sqrt{\frac{0,01}{1,21}}+3\frac{2}{\sqrt{10^2+2^2+40}}-\frac{3}{4}\)
Tính \(A=\frac{1}{2.\sqrt{1}+1.\sqrt{2}}+\frac{1}{3\sqrt{2}+2\sqrt{3}}+\frac{1}{4\sqrt{3}+3\sqrt{4}}+....+\frac{1}{100.\sqrt{99}+99.\sqrt{100}}\)
1.Chứng tỏ rằng:
A=75.(42004+42003+...+42+4+1)+25 chia hết cho 100
2.tính nhanh:
\(A=\frac{\left(1+2+3+...+99+100\right)\left(\frac{1}{2}-\frac{1}{3}-\frac{1}{7}-\frac{1}{9}\right)\left(63.1,2-21.3,6\right)}{1-2+3-4+...+99-100}\)
\(B=\frac{\left(\frac{1}{14}-\frac{\sqrt{2}}{7}+\frac{\sqrt[3]{2}}{35}\right).\left(-\frac{4}{15}\right)}{\left(\frac{1}{10}+\frac{\sqrt[3]{2}}{25}-\frac{\sqrt{2}}{5}\right).\frac{5}{7}}\)
3.a)tính giá trị của biểu thức A=3x2-2x+1 với |x|=\(\frac{1}{2}\)
b)Tìm x nguyên để \(\sqrt{x+1}\)chia hết cho \(\sqrt{x-3}\)
Bài 1:
a) \(26\frac{1}{7}:\left(-\frac{3}{4}\right)-44\frac{1}{7}:\left(-\frac{3}{4}\right)\)
b) \(10.\sqrt{0,01}-\left(-\frac{1}{2}\right)^3-\frac{1}{2}.\sqrt{4}+0,25\)
Tìm x , biết :
a) \(\sqrt{16}\)x + \(\frac{3}{4}\)= 2 \(\sqrt{\frac{4}{25}}\)+ 0,01 . \(\sqrt{100}\)
b) \(\left(x-\frac{2}{5}\right)\)\(\left(x+\frac{3}{7}\right)\)= 0
Tìm x
a. \(\sqrt{16x}\)\(+\frac{3}{4}\)\(=2\sqrt{\frac{4}{25}}\)\(+0,01.\sqrt{100}\)
b. \(2\frac{3}{4}x\)\(=3\frac{1}{7}\)\(:0,01\)
c. \(|x|\)\(+3^2\)\(=2^2\)\(+\left(\frac{1}{2}\right)^3\)
Tính: \(B=\left(\frac{10\sqrt{1,21}}{7}+\frac{22\sqrt{0,25}}{3}\right):\left(\frac{5}{\sqrt{49}}+\frac{\sqrt{225}}{9}\right)\)
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 \(B=1+\frac{1}{2}\left(1+2\right)+\frac{1}{3}\left(1+2+3\right)+\frac{1}{4}\left(1+2+3+4\right)+...+\frac{1}{20}\left(1+2+3+...+20\right)\)