a) Để y dương thì 2a-1 < 0
=> 2a < 1
=> a < \(\frac{1}{2}\)
b) Để y âm thì 2a-1 > 0
=> 2a > 1
=> a > \(\frac{1}{2}\)
c) Để y ko âm, ko dương thì 2a-1 = 0
=> 2a = 1
=> a = \(\frac{1}{2}\)
Tick cho mik nha
Cho minh hoi bai nay. Chi can tra loi 1 cau cung duoc! Tick cho ai tra loi som nhat, day du nhat.
1. Cho so huu ti y=2a-1/-3. Voi gia tri nao cua a thi y la so duong, y la so am, khong phai so duong cung phai so am?
2. Cho so huu ti x=a-5/a (a khac 0). Voi gia tri nao cua a thi x la so nguyen?
3. Cho so huu ti x=a-3/2a (a khac 0). Voi gia tri nao cua a thi x la so nguyen?
cho 2 so huu ti x= 2a+7/5 va y = 3b-8/-5 voi gia tri nao cua a,b thi
a) x,y la so huu ti duong
b) x,y la so huu ti am
c) x,y khong la so huu ti am khong la so huu ti duong
ai tra loi nhanh ,dung mk tick cho
cho so huu ti x=2a-1/2 voi gia tri nao cua a thi
A .x la so duong
B .x la so am
C .x khong la so huu ti duong cung ko phai lai so huu ti am
giup mk nha
Cho truoc diem a va duong thang d di qua diem a ve 2018 duong thang phan biet . goi x la so duong thang vuong goc voi d, y la so duong thang khong vuong goc void trong 2018 duong thang da cho..
Tim gia tri nguyen lon nhat cua x, y
Tim gia tri nguyen nho nhat cua x,y
Trong cac cau sau day , cau nao dung , cau nao sai ?
a) Neu a la so nguyen thi a cung la so thuc .
b) Chi co so 0 khong la so huu ti duong va cung khong la so huu ti am .
c) Neu a la so tu nhien thi a khong phai la so vo ti .
Cho so huu ti x=\(\frac{a-3}{2}\)
Voi gia tri nao cua xthi
a ) la so nguyen duong
b) la so nguyen am
c) x ko la duong cung ko am
CHO số hạng A x=a-3 phần 2.Với gía trị cũa a thì
a]x là số duong
b]x là so am
c]x khong phai la so duong cung khong phai la so am
cho so huu ti \(y=\frac{a-3}{a}\)
a,voi gt nao cua a thi x la so duong
b,voi gt nao cau a thi x la so am
c,voi gt nao cua a thi x la so nguyen
bai 1 tim cac stn x y z sao cho x+y+z=xyz
bai 2cmr neu m^2+mn+n^2chia het cho 9 voi m ,n la cac stn thi m,n chia het cho 3
bai 3 tim stn n nho nhat de cac phan so sau toi gian
7/n+9.8/n+10,...,31/n+33
bai 4chung to rang phan so m^3+2m/m^4+3m^2 +1 toi gian
bai 5 a,cmr khong ton tai so chinh phuong nao co dang abab
b,cho 51 so nguyen duong khong vuot qua 100 cmr ton tai 2 so trong 51 so noi tren ma 1 so chia het cho so con lai
c,tim cac so co 3 chu so sao cho hieu cua so ay va gom 3 chu so ay viet theo thu tu nguoc lai la mot so chinh phuong
bai 6cmr A=2x(x+y-1)+y^2+1 luon nhan gia tri khong am voi moi x,y
bai 7 tim hai so nguyen duong sao cho tong ,hieu thuong (so lon chia cho so nho )cua chung cong lai duoc 38
bai 8 cho ba so a,b,c thoa man a/2009=b/2010=c/2011
tinh gia tri cua bieu thuc M=4(a-b)(b-c)-(c-a)^2
