Cho A=1+2020+2020^2+...+2020^98
So sanh A voi 2020.2020^98-2
Giup minh nhe!
So sanh giua 2*2019-1 voi 202099*2018
Giup minh nhanh nhe!
nhìn là biết rồi,cái bên trái
A=2020/2020/mu2017/2016/+1/+1 B= 2020/2020/mu2016/2015+1/+1 so sanh jup minh vs
cho A= 1+2020+20202+20203+20204+20205+.......+202097+202098. So sánh A với 2020x202098-2
A=2020^100-1:2020^99+1 so sanh a va b
B=2020^101-1:2020^100+1
so sanh A=2020^2018-1/2020^2019-2019 và B=2020^2019+1/2020^2020+2019
so sanh 2 phan so sau:
\(\frac{2017}{1019}\)va \(\frac{2018}{2020}\)
ai tra loi duoc thi ket ban voi minh nhe
Ta có:
\(\frac{2017}{2019}=1-\frac{2}{2019}\)
\(\frac{2018}{2020}=1-\frac{2}{2020}\)
Vì \(\frac{2}{2019}>\frac{2}{2020}\)
=> \(1-\frac{2}{2019}>1-\frac{2}{2020}\)
=> \(\frac{2017}{2019}>\frac{2018}{2020}\)
\(\frac{2017}{1019}>\frac{2018}{2020}\)
Ta có: \(2017>1019\)
\(\Rightarrow\frac{2017}{1019}>1\)
\(\Rightarrow\frac{2017}{1019}>\frac{2017+1}{1019+1}=\frac{2018}{1020}>\frac{2018}{2020}\)
Vậy \(\frac{2017}{1019}>\frac{2018}{2020}\)
so sanh 2 phan so
A = 10^2020+1/10^2021+1
B = 10^2021+1/10^2022+1
giup mik luon voi a
thank
\(10A=\dfrac{10^{2021}+1+9}{10^{2021}+1}=1+\dfrac{9}{10^{2021}+1}\)
\(10B=\dfrac{10^{2022}+1+9}{10^{2022}+1}=1+\dfrac{9}{10^{2022}+1}\)
mà \(10^{2021}+1< 10^{2022}+1\)
nên A>B
So sanh voi 0
2019 . (-1) . 2 . (-3) . (-9) . 2020 . (-11) . 59 . (-7)
2019.(-1).2.(-3).(-9).2020.(-11).59.(-7) <0
vì có 5 dấu âm
âm.dương = âm
âm.âm=dương
âm.âm.âm=âm
voi moi a>2020. tim gtnn cua a=a+1/a-2020
\(a=\dfrac{a+1}{a-2020}\)
\(=\dfrac{a-2020}{a-2020}+\dfrac{2021}{a-2020}\)
\(=1+\dfrac{2021}{a-2020}\) Vì a>2020
⇒\(1+\dfrac{2021}{a-2020}\text{≥}2\)
Min a=2 ⇔\(\dfrac{2021}{a-2020}=1\)
⇔\(a-2020=2021\)
⇔\(a=4041\)