f(x)+f(1-x)= -1. Chứng minh hay dùng máy tính thì tùy bạn.
Kết quả: S=-505
f(x)+f(1-x)= -1. Chứng minh hay dùng máy tính thì tùy bạn.
Kết quả: S=-505
1) ABC is a triangle where M is the midpoint of segment BC.
MD and ME are two bisectors of triangles AMB and AMC respectively.
If AM= m; BC = a . Then DE = ???
2)\(\dfrac{1}{\left(x+29\right)^2}+\dfrac{1}{\left(x+30\right)^2}=\dfrac{5}{4}\)
What is the product of all real solutions to the equation above?
3) The sum of all possible natural numbers n such that
\(n^2+n+1589\) is a perfect square is.....
4) Given that x is a positive integer such that x and x+99 are perfect squares
The sum of integer x is ...
5)The operation @ on two numbers produces a number equal to their sum minus 2. The value of
(...((1@2)@3....@2017)
6) Given f(x)=\(\dfrac{x^2}{2x-2x^2-1}\)
=> \(f\left(\dfrac{1}{2016}\right)+f\left(\dfrac{2}{2016}\right)+f\left(\dfrac{3}{2016}\right)+...+f\left(\dfrac{2016}{2016}\right)\)
Các bn giúp mk vs >>> tks nha!!!
a) Tìm x(x thuộc N*), biết \(\left(1+\dfrac{1}{1.3}\right)\left(1+\dfrac{1}{2.4}\right)\left(1+\dfrac{1}{3.5}\right)...\left(1+\dfrac{1}{x\left(x+2\right)}\right)=\dfrac{31}{16}\)
b) Chứng tỏ \(\dfrac{2}{2^2}+\dfrac{2}{4^2}+\dfrac{2}{6^2}+...+\dfrac{2}{2016^2}< \dfrac{2016}{2017}\)
c) Chứng tỏ \(\dfrac{1}{5^2}+\dfrac{1}{9^2}+\dfrac{1}{13^2}+...+\dfrac{1}{41^2}< \dfrac{10}{129}\)
a)giải phương trình sau
\(\left(3x^2+x-2016\right)^2+4\left(x^2+506x-2017\right)^2=4\left(3x^2+x-2016\right).\left(x^2+506x-2017\right)\)
b) tìm đa thức f(x) biết rằng f(x) chia cho x+3 duw, f(x) chia cho x-2duw 6, f(x) chia cho x2+x-6 được thương là 2x và còm dư
Tính: \(C=2x-2y+13x^3y^2.\left(x-y\right)+15\left(y^2x-x^2y\right)+\left(\dfrac{2015}{2016}\right)^0\)
biết x - y = 0
F=(11 2x−2y 2(x−y)−1):(2x−2y−(4x2−8xy 4y22x−2y 1))F=(11 2x−2y 2(x−y)−1):(2x−2y−(4x2−8xy 4y22x−2y 1))F=\left(\dfrac{1}{1 2x-2y} 2\left(x-y\right)-1\right):\left(2x-2y-\left(\dfrac{4x^2-8xy 4y^2}{2x-2y 1}\right)\right) Cm giá trị của F là một số chẵn vs mọi x,
tính :P=\(\dfrac{\left(2016^2\cdot2026+31\cdot2017-1\right)\left(2016\cdot2021+4\right)}{2017\cdot2018\cdot2019\cdot2020\cdot2021}\)
Giải các phương trình sau:
a) \(x^2+\dfrac{2x}{x-1}=8\)
b) \(\dfrac{x^2+2x+1}{x^2+2x+2}+\dfrac{x^2+2x+2}{x^2+2x+3}=\dfrac{7}{6}\)
c) \(\dfrac{x+4}{x-1}+\dfrac{x-4}{x+1}=\dfrac{x+8}{x-2}+\dfrac{x-8}{x+2}+6\)
d) \(\left(x^2+6x+8\right)\left(x^2+8x+15\right)=24\)
e) \(\left(x^2+x-2\right)\left(x^2+9x+18\right)=28\)
f) \(3\left(-x^2+2x+3\right)^4-26x^2\left(-x^2+2x+3\right)^2-9x^4=0\)
g) \(x^4+6x^3+11x^2+6x+1=0\)
h) \(\left(x-3\right)\left(x-5\right)\left(x-6\right)\left(x-10\right)-24x^2=0\)
i) \(\left(x+2\right)^4+\left(x+8\right)^4=272\)
Chúng minh đẳng thức:
\(\dfrac{2}{x\left(x+1\right)}+\dfrac{2}{\left(x+1\right)\left(x+2\right)}+\dfrac{2}{\left(x+2\right)\left(x+3\right)}+...+\dfrac{2}{\left(x+2014\right)\left(x+2015\right)}=\dfrac{4030}{x\left(x+2015\right)}\)
\(\dfrac{2}{2^2-x^2}+\dfrac{1}{2x+x^2}\)
=\(\dfrac{2}{\left(2-x\right)\left(2+x\right)}+\dfrac{1}{x\left(x+2\right)}\)
=\(\dfrac{2x}{x\left(2-x\right)\left(2+x\right)}+\dfrac{\left(2-x\right)}{x\left(2-x\right)\left(2+x\right)}\)
=\(\dfrac{2x+2-x}{x\left(2-x\right)\left(2+x\right)}\)
=\(\dfrac{x+2}{x\left(2-x\right)\left(2+x\right)}\)