Các câu hỏi tương tự
tim x cau 1: |x-2|=10
cau 2:15-x^2=-21 cau 3: x.(x+7)=0
cau 1,(n^2-7)\(⋮\)n+3
cau 2 tim x;y;z
bietx-y=-9
y-z=-10
z+x=11
giup minh voi cac ban :
1timx
5^x-2-3^2=2^4-(2^8.2^4-2^10.2^2)
697:[(15^x+364):x]=17
134:(x-3)=35+160:5
(3.x-2^4).7^3=2.7^4
[(10-x) .2+5]:3-2=3
2 tim x thuoc N
cau a : n+5chia het n +1
cau b :2.n +7 chia het cho n-2
Cau 1:
Tim x, biet: 1-4+7-10+.............-x=-75
Cau 2:
Cho x1, x2, x3, x4, x5 thuộc Z
Biết x1+ x2 + x3 + x4 + x5=0
và x1 + x2=x3+ x4= x4 + x5 =2
Tinh x3, x4 , x5
Cau 3: Tim x biet
(x+7+1) chia het cho (x+7)
Cau 1:
- 2-(9-36)
Cau 2: tim cac so tu nhien n sao cho (2n+9) chia het cho (n+1)
Cau3:goi x la tong cac chu so cua so a =32010+2011, goi y la tong cac chu so cua so x va goi z la tong cac chu so cu y . tim z
cau 1 tinh
C=1^2+2^2+...99^2
Cau 2
Tim x\(\inℤ\)biet
(x-3)+(x-2)+(x-1)+...+10+11
Cau 3
cho x;y\(\inℤ\)
biet 5.x+47.y\(⋮\)17
CM x+6y\(⋮\)17
1 cau =1 tick
Tim cac so nguyen x,y biet
Cau a, x /10-1/y=3/10
Cau 1 .Cho A = 3/4 + 8/9 + 15/16 +…+ 9999/10000
Chung to a lon hon 4/3
CAU 2 . A = x/x+y + y/y+z +x/x+z
Cho z , y z thuoc N* chung to A k thuoc N
Cau 1: Tim n biet : 5/8 + 5/24 + 5/48 + 5/80 + ... + 5/2n + 2 . 2n + 4 = 189/112
Cau 2 : Cho A = 1 + 1/1.2 + 1/1.2.3 + ... + 1/1.2.3...2014. So sanh A voi 2
Cau 3 : Tim n biet : 5/3 + 5/15 + 5/35 + 5/63 +...+ 5/2n + 1 . 2n + 3 = 172/69