A;|x-3|-7=-4
|x-3| =-4+7
|x-3| =3
suy ra x-3=3 hoac x-3=-3
TH1:x-3=3 thi x=6
TH2:x-3=-3 thi x=0
vay x=6 hoac =0
o ket luan cong 2 so nguyen cung dau
Biet a thuoc Z , tim so nguyen x :
a + x = 5
Ai nhanh la tick
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
tim so nguyen n, biet:
(x+7)(x-8)=0
Ai lam nhanh nhat minh tick cho
tim x thuoc N biet 97.x la so nguyen to ( . la dau nhan)
Tim so nguyen n, biet:
x(x-3)=0
Ai lam nhanh nhat minh tick cho.
bai1
tim x biet rang tong cua 4 so
x; (-5);7 va (-15)=1
bai 2
tim so nguyen a biet
a] |a-15|=0
b] |a+7|=2
nhanh minh dang gap minh like
tim so nguyen X Y thuoc Z biet
(X-7) x (X x Y + 1)=7
giai gium minh nha !!!!
thank you very much !!!!!!!!!!!!!!
Bai 1: a)Tim so tu nhien a biet 1960va2002 chia cho a cung co so du la 28
b)Tim 2 sop tu nhien a va b , biet :BCNN(a,b)=300;UCLN(a,b)=15 va a+15=b
Bai 2:a)Tong sau la binh phuong so nao ?
S=1+3+5+7+...+199
b) Cho so ab va so ababab
1)chung to ababab la boi cua ab
2)So 3 va 10101 co phai la uoc cua ababab khong , vi sao?
Bai 3
a)Hay viet them dang sau so 664 ba chu so de nhan duoc sdo co 6 chu so chia het cho 5,9,11
b)Tim so nguyen x thuoc Z biet rang :
(x^2-1)(x^2-4)<0
Bai 4 :tim so nguyen x va y biet: xy-x+2y=3
tim x dua vao quan he uoc boi:
tim so tu nhien x sao cho x-1 la uoc cua 12
tim so tu nhien x sao cho 2x+1 la uoc cua 28
tim so tu nhien x sao cho x+15 la boi cua x+3
tim cac so nguyen x,y sao cho (x+1)(y-2)=3
tim so nguyen x sao cho(x+2).(y-1)=2
tim so nguyen to x vua la uoc cua 275 vua la uoc cua 180
tim so nguyen to x,y biet x+y=12 va UCLL (x:y)=5
tim so tu nhien x,y biet x+y=32 va UCLL (x:y)=8
tim so tu nhien x biet x chia het cho10; xchia het cho12; x chia het cho15 va 100<x<150
tim so x nho nhat khac 0b biet x chia het cho 24 va 30
40 chia het cho x . 56 chia het cho x va x>6
