1 . (52015 + 52014) : (52014 + 52013)
= (52015 + 52014) : (52014 + 52013)
= 5 : 5
= 1.
=(5^2015+5^2014):(5^2014+5^2013).....suy ra =...5:...5 chia hêt cho 5
Chứng minh rằng 1 . 3 . 5. ... . 2013 . 2015 + 2 . 4 . 6 . ... . 2014 . 2016 chia hết cho 9911
Tìm x
a,x/15=2/5
b,3/x-7=27/135
c,320.x-10=5.48:24
d,5.x-1952=2500-1947
e,(x+1)+(x+2)+(x+3)+(x+4)+(x+5)=45
f,x-2/3-2/15-2/35-2/63=1/9
g,(x-1.3/4).3/2.2+1/2-3/2=2
h,2/6+2/12+2/20+...+2/x.(x+14)=2013/2015
k,3+5+7+...+2015/2+4+6+...+2014+x=1
tinh:
a,A=1+2+3+........+2015
b,B=1+2+5+.........+1017
c,C=2+4+6+..........+2014
d,D=1+4+7+...........+2008
e,E=1.2+2.3+3.4+................1001+1002
tinh:
a,A=1+2+3+........+2015
b,B=1+2+5+.........+1017
c,C=2+4+6+..........+2014
d,D=1+4+7+...........+2008
e,E=1.2+2.3+3.4+................1001+1002
tinh:
a,A=1+2+3+........+2015
b,B=1+2+5+.........+1017
c,C=2+4+6+..........+2014
d,D=1+4+7+...........+2008
e,E=1.2+2.3+3.4+................1001+1002
tinh:
a,A=1+2+3+........+2015
b,B=1+2+5+.........+1017
c,C=2+4+6+..........+2014
d,D=1+4+7+...........+2008
e,E=1.2+2.3+3.4+................1001+1002
tinh:
a,A=1+2+3+........+2015
b,B=1+2+5+.........+1017
c,C=2+4+6+..........+2014
d,D=1+4+7+...........+2008
e,E=1.2+2.3+3.4+................1001+1002
Viết tích sau dưới dạng một lũy thừa: x . x2 . x3 . x4 . x5 . ... . x2013 . x 2014
Bài 1:
a. \(\left(5^{2010}+5^{2012}+5^{2014}\right):\left(5^{2011}+5^{2009}+5^{2007}\right)\)
b. \(\left(-\dfrac{7}{45}\right)-\left(-\dfrac{1}{4}\right)-\left(-\dfrac{3}{5}\right)+\dfrac{1}{12}+\dfrac{2}{3}+\dfrac{1}{39}-\left(-\dfrac{5}{9}\right)\)
