Tìm x biết:
2/(x+2)(x+4)+ 4/(x+4)(x+8)+6/(x+8)(x+14)=x/(x+2)(x+14)
1/Tính :
a. A= 1/17+ 7/17.27 + 7/27.37 + .................... +7/1997.2007
b. B=-1/2007.2006 - 1/2005.2006 - 1/2005.2004 - .................... - 1/3.2 - 1/2.1
2/Tim x biết :
2/(x+2)(x+4) + 4/(x+4)(x+8) + 6/(x+8)(x+14) = x/(x+2)(x+14)
Với x không thuộc tập hợp {-2;-4;-6;-8;-14}
\(\dfrac{2}{(x + 2)(x + 4)}+\dfrac{4}{(x + 4)(x + 8)}+\dfrac{6}{(x + 8)(x + 14)}=\dfrac{x}{(x + 2)(x + 14)}\)
\(\dfrac{2}{\left(x+2\right)\left(x+4\right)}+\dfrac{4}{\left(x+4\right)\left(x+8\right)}+\dfrac{6}{\left(x+8\right)\left(x+14\right)}=\dfrac{x}{\left(x+2\right)\left(x+14\right)}\)
2. Tìm x biết:
a)\(\dfrac{2}{\left(x+2\right)\left(x+4\right)}\) + \(\dfrac{4}{\left(x+4\right)\left(x+8\right)}\) + \(\dfrac{6}{\left(x+8\right)\left(x+14\right)}\) = \(\dfrac{x}{\left(x+2\right)\left(x+14\right)}\).
b)\(\dfrac{x}{2023}\) + \(\dfrac{x+1}{2022}\) + \(\dfrac{x+2}{2021}\) +...+ \(\dfrac{x+2022}{1}\) + 2023 = 0.
Gíup mình giải 2 bài này với!
Cảm ơn các bạn rất nhiều!!!
\(\frac{2}{\left(x+2\right)\left(x+4\right)}\)+\(\frac{4}{\left(x+4\right)\left(x+8\right)}\)+\(\frac{6}{\left(x+8\right)\left(x+14\right)}\)=\(\frac{x}{\left(x+2\right)\left(x+14\right)}\)
với x ko thuộc {-2;-4;-6;-8;-14}
\(\frac{2}{\left(x+2\right).\left(x+4\right)}+\frac{4}{\left(x+4\right).\left(x+8\right)}+\frac{6}{\left(x+8\right).\left(x+14\right)}=\frac{x}{\left(x+2\right).\left(x+14\right)}\)
\(\frac{2}{\left(x+2\right)\left(x+4\right)}+\frac{4}{\left(x+4\right)\left(x+8\right)}+\frac{6}{\left(x+8\right)\left(x+14\right)}=\frac{x}{\left(x+2\right)\left(x+14\right)}\)
Tìm x
\(\frac{2}{\left(x+2\right).\left(x+4\right)}+\frac{4}{\left(x+4\right).\left(x+8\right)}+\frac{6}{\left(x+8\right).\left(x+14\right)}=\frac{x}{\left(x+2\right).\left(x+14\right)}\)