7 tim x thuoc Z
-1 + 3 + (-5) +7 +.......+x = 600
tim x thuoc z
(-1)+3+(-5)+7+...+x=600
bai 1:tim x
a) (x+1/5)2+17/25=26/25
b)-1va 5/27-(3x-7/9)3=-24/27
bai 2:cho A=n+2/n-5 (n thuoc Z ;n khac 5).Tim x de A thuoc Z
bai 1 tim so nguyen duong nho nhat co 3 chu so , so nguyen a lon nhat co 2 chu so
bai 2: tim x thuoc Z biet
a, / x/ = -5
b, /x/= <7
c, /x/ = 4
d, /x/=0
Bai 1: Tinh nhanh:
a, -69+53+46+(-14)+78 b, 13-12+11+10-9+8-7-6+5-4+3+2-1
Bai 2: a,Tim gia tri nho nhat cua bieu thuc: A= |x+19|+|y-5|+1890
b, Tim gia tri lon nhat cua bieu thuc: B= -|x-7|-|y+13|+1945
Bai 3: Tim x,y thuoc Z biet: a, xy-3x= -19 b, 3x+4y-xy= 16
Bai 4: Tim x thuoc Z biet: a, x.(x+3)= 0 b, (x-2) (5-x)= 0 c, (x+1) (x2+1)= 0
d, -12 (x-5)+7 (3-x)= 5 e, 30 (x+2)-6 (x-5)-24x= 100 f, (x+1)+(x+3)+(x+5)+. . .+(x+99)= 0
Minh xin cam on truoc ! THANK YOU
1 )Tim x, y thuoc Z
x + y = x.y
2) Tim x thuoc Z
(x + 1)+(x+3)+(x+5)+...+(x+99)=0(x-3)+(x-2)+(x-1)+...+10+11=11-12(x-5)+7(3-x)=530(x+2)-6(x-5)-24x=100Bai 1:Cho A=5- 5^2 + 5^3 - 5^4 +...-5^98 + 5^99 . Tinh tong A.
Chung to (2^n + 1)x( 2^n +2) chia het cho 3 voi moi n la so tu nhien.
Bai 2 :Tim n thuoc Z de (4n-3) chia het cho (3n-2)
bai tim x,y thuoc z biet
a,/-x/-(-4)=3
cac ban giu toi giai bai tap nay nhe.
tim x thuoc z
A) |2x-5|=13
(x-1)*(x ^2+1)=0