Ôn tập toán 8
Các câu hỏi tương tự
a) Tính \(S=\left(-\frac{1}{7}\right)^0+\left(-\frac{1}{7}\right)^1+\left(-\frac{1}{7}\right)^2+...+\left(-\frac{1}{7}\right)^{2017}\)
b) So \(\frac{1}{2!}+\frac{2}{3!}+\frac{3}{4!}+...+\frac{99}{100!}\) với \(1\)
\(P=\frac{\frac{1}{99}+\frac{2}{98}+\frac{3}{97}+...+\frac{99}{1}}{\frac{1}{2}+\frac{2}{3}+\frac{1}{4}+...+\frac{1}{100}}\)
\(Q=\frac{92-\frac{1}{9}-\frac{2}{10}-\frac{3}{11}-...-\frac{92}{100}}{\frac{1}{45}+\frac{1}{50}+\frac{1}{55}+...+\frac{1}{500}}\)
a) Tính P, Q
b) Tính tỉ số % của P và 3Q
a) So sánh : \(\sqrt{17}+\sqrt{26}+1va`\sqrt{99}\)
b) Chứng minh \(\frac{1}{\sqrt{1}}+\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{3}}+...+\frac{1}{\sqrt{100}}>10\)
a) So \(M=\left(\frac{1}{2^2}-1\right)\left(\frac{1}{3^2}-1\right)\left(\frac{1}{4^2}-1\right)...\left(\frac{1}{100^2}-1\right)vs-\frac{1}{2}\)
b) \(N=\frac{\sqrt{x}+1}{\sqrt{x}-3}\). Tìm \(x\in Z\) để \(N\)là số nguyên dương
giải phương trình
a,\(\left(\frac{1}{1\cdot2}+\frac{1}{2\cdot3}+\frac{1}{3\cdot4}+\frac{1}{9\cdot10}\right)\left(x-1\right)+\frac{1}{10}x=x-\frac{9}{10}\)
b,\(\frac{x+1}{1}+\frac{2x+3}{3}+\frac{3x+5}{5}+\frac{20x+39}{39}=22+\frac{4}{3}+\frac{6}{5}+\frac{40}{39}\)
c,(x-20)+(x-19)+(x-18)+...+100+101=101
Tìm x : \(\frac{2x-\frac{x-1}{2}}{3}-\frac{\frac{x+1}{2}-\frac{2x-3}{3}}{2}=\frac{\frac{x-1}{2}-1}{3}-\frac{x-3}{4}\)
giải phương trìnha,(frac{1}{1cdot2}+frac{1}{2cdot3}+frac{1}{3cdot4}+frac{1}{9cdot10})(x-1)+frac{1}{10}xx-frac{9}{10}b,frac{x+1}{1}+frac{2x+3}{3}+frac{3x+5}{5}+frac{20x+39}{39}22+frac{4}{3}+frac{6}{5}+frac{40}{39}c,(x-10)+(x-19)+(x-18)+...+100+101101d,(frac{1}{1cdot51}+frac{1}{2cdot52}+frac{1}{3cdot53}+...+frac{1}{10cdot60})xfrac{1}{1cdot11}+frac{1}{1cdot12}+frac{1}{1cdot13}
Đọc tiếp
giải phương trình
a,(\(\frac{1}{1\cdot2}+\frac{1}{2\cdot3}+\frac{1}{3\cdot4}+\frac{1}{9\cdot10}\))(x-1)+\(\frac{1}{10}x\)=\(x-\frac{9}{10}\)
b,\(\frac{x+1}{1}+\frac{2x+3}{3}+\frac{3x+5}{5}+\frac{20x+39}{39}=22+\frac{4}{3}+\frac{6}{5}+\frac{40}{39}\)
c,(x-10)+(x-19)+(x-18)+...+100+101=101
d,(\(\frac{1}{1\cdot51}+\frac{1}{2\cdot52}+\frac{1}{3\cdot53}+...+\frac{1}{10\cdot60}\))x=\(\frac{1}{1\cdot11}+\frac{1}{1\cdot12}+\frac{1}{1\cdot13}\)
giúp mình với
làm phép tính
c) \(\frac{1}{3x-2}-\frac{4}{3x+2}-\frac{3x-6}{4-9x^2}\)
d) x - 2 \(-\frac{x^2-10}{x+2}\)
e)\(\frac{1}{2x-2y}-\frac{1}{2x+2y}+\frac{y}{y^2-x^2}\)
g)\(\frac{4-2x+x^2}{x+2}-2-x\)
i)\(\frac{1}{2x+3}-\frac{1}{2x-3}+\frac{x-2}{2x^2-x-3}\)
Tìm x: \(\frac{\frac{1}{2}-\frac{x+2}{3}}{2}-\frac{2}{3}\left(x+1\right)=\frac{1}{4}\left(1-2x\right)-\frac{\frac{1}{3}-\frac{1-x}{2}}{2}\)