Violympic toán 8
Các câu hỏi tương tự
Giải các phương trình sau
a,\(\dfrac{6x+5}{2}-\dfrac{10x+3}{4}=2x+\dfrac{2x+1}{2}\)
b,\(\left(x-4\right)\left(x+4\right)-2\left(3x-2\right)=\left(x-4\right)^2\)
1) Cho P left(dfrac{4x-x^3}{1-4x^2}-xright):left(dfrac{4x^2-x^4}{1-x^2}+1right)
a) rút gọn b) tìm x để P 0
2) Cho Q left(dfrac{x}{x^2-3x+9}-dfrac{11}{x^3+27}+dfrac{1}{x+3}right):dfrac{x^2-1}{x+3}
a) rút gọn b) tìm GTLN
3) Cho A dfrac{1}{left(x-yright)^3}left(dfrac{1}{x^3}-dfrac{1}{y^3}right)+dfrac{3}{left(x-yright)^4}left(dfrac{1}{x^2}+dfrac{1}{y^2}right)+dfrac{6}{left(x-yright)^5}left(dfrac{1}{x}+dfrac{1}{y}right)
chứng minh A là lập phương một số hữu tỉ
Đọc tiếp
1) Cho P = \(\left(\dfrac{4x-x^3}{1-4x^2}-x\right):\left(\dfrac{4x^2-x^4}{1-x^2}+1\right)\)
a) rút gọn b) tìm x để P > 0
2) Cho Q = \(\left(\dfrac{x}{x^2-3x+9}-\dfrac{11}{x^3+27}+\dfrac{1}{x+3}\right):\dfrac{x^2-1}{x+3}\)
a) rút gọn b) tìm GTLN
3) Cho A = \(\dfrac{1}{\left(x-y\right)^3}\left(\dfrac{1}{x^3}-\dfrac{1}{y^3}\right)+\dfrac{3}{\left(x-y\right)^4}\left(\dfrac{1}{x^2}+\dfrac{1}{y^2}\right)+\dfrac{6}{\left(x-y\right)^5}\left(\dfrac{1}{x}+\dfrac{1}{y}\right)\)
chứng minh A là lập phương một số hữu tỉ
Giải các phương trình sau:
1. \(a,\dfrac{6}{x-1}-\dfrac{4}{x-3}=\dfrac{8}{2x-6}\)
\(b,\dfrac{1}{x-2}+\dfrac{5}{x+1}=\dfrac{3}{2-x}\)
\(c,\dfrac{3x}{x-2}-\dfrac{x}{x-5}=\dfrac{3x}{\left(x-2\right)\left(5-x\right)}\)
2. \(a,\left(x+2\right)\left(3-4x\right)=x^2+4x+4\)
\(b,2x^2-6x+1\)
rút gọn biểu thức A=\(\left(\dfrac{10x-5}{x^2-9}-\dfrac{3-x}{x+3}\right):\dfrac{x+2}{x+3}\)
Bài 7: Giải các phương trình sau :
a) \(\frac{x+1}{9}+\frac{x+2}{8}=\frac{x+3}{7}+\frac{x+4}{6}\)
b) \(\frac{x+2}{98}+\frac{x+4}{96}=\frac{x+6}{94}+\frac{x+8}{92}\)
c) \(\frac{2-x}{2002}-1=\frac{1-x}{2003}-\frac{x}{2004}\)
d) \(\frac{x^2-10x-29}{1971}+\frac{x^2-10x-27}{1973}=\frac{x^2-10x-1971}{29}+\frac{x^2-10x-1973}{27}\)
Bài 1:cho phương trình
a,left(x-1right)^3-xleft(x-1right)^25xleft(2-xright)-11left(x+2right)
b,dfrac{left(x+10right)left(x+4right)}{12}-dfrac{left(x+4right)left(2-xright)}{4}dfrac{left(x+10right)left(x-2right)}{3}
c,dfrac{2left(x-3right)}{7}+dfrac{x-5}{3}dfrac{13x+4}{21}
d,dfrac{2x-1}{5}-dfrac{x-2}{3}dfrac{x+7}{5}
e,left(x-2right)^3+left(3x-1right)left(3x+1right)left(x+1right)^3
Đọc tiếp
Bài 1:cho phương trình
a,\(\left(x-1\right)^3-x\left(x-1\right)^2=5x\left(2-x\right)-11\left(x+2\right)\)
b,\(\dfrac{\left(x+10\right)\left(x+4\right)}{12}-\dfrac{\left(x+4\right)\left(2-x\right)}{4}=\dfrac{\left(x+10\right)\left(x-2\right)}{3}\)
c,\(\dfrac{2\left(x-3\right)}{7}+\dfrac{x-5}{3}=\dfrac{13x+4}{21}\)
d,\(\dfrac{2x-1}{5}-\dfrac{x-2}{3}=\dfrac{x+7}{5}\)
e,\(\left(x-2\right)^3+\left(3x-1\right)\left(3x+1\right)=\left(x+1\right)^3\)
( \(\dfrac{x+1}{2\left(x-1\right)}+\dfrac{3}{x^2-1}-\dfrac{x+3}{2x+2}\) ). \(\dfrac{4x^2-4}{5}\)
\(\dfrac{x}{x-3}-\dfrac{x^2+3x}{2x+3}.\left(\dfrac{x+3}{x^2-3x}-\dfrac{x}{x^2-9}\right)\)
\(\left(\dfrac{x+1}{x}\right)^2:\left(\dfrac{x^2+3}{x^2}+\dfrac{2}{x+1}.\left(\dfrac{1}{x}+1\right)\right)\)
Thực hiện phép tính:
\(a,\dfrac{1}{x\left(x+1\right)}+\dfrac{1}{\left(x+1\right)\left(x+2\right)}+\dfrac{1}{\left(x+2\right)\left(x+3\right)}+\dfrac{1}{\left(x+3\right)\left(x+4\right)}\)
\(b,\dfrac{1}{x^2+3x+2}+\dfrac{1}{x^2+5x+6}+\dfrac{1}{x^2+7x+12}+\dfrac{1}{x^2+9x+20}\)
giải pt: \(\dfrac{1}{\left(x-1\right)\left(x-2\right)}+\dfrac{1}{\left(x-3\right)\left(x-2\right)}=\dfrac{1}{\left(x-3\right)\left(x-4\right)}+\dfrac{1}{\left(x-1\right)\left(x-4\right)}\)