B=\(\frac{5}{\sqrt{x}-1}\). Tim x thuoc Z de B co gia tri nguyen.
cho P=\(\frac{9}{\sqrt{x-5}}\). tim x thuoc Z de A co gia tri nguyen
Cho A=n+1/n-2
a)Tim n thuoc Z de A co gia tri nguyen.
b)Tim n thuoc de A co gia tri nguyen lon nhat.
cho bieu thuc: M=x^2-5 phan x^2 (x thuoc Z)
Tim x thuoc Z de M co gia tri nguyen
Cho bthuc: \(A=\frac{1}{2\sqrt{x}-2}-\frac{1}{2\sqrt{x}+2}+\frac{\sqrt{x}}{1-x}\)
a) Rut gon A
b) Tim gia tri cua x de /A/ =\(\frac{1}{2}\)
c) Tim x nguyen de A co gia tri nguyen
TIm x thuoc Z de cac ps sau co gia tri la so nguyen :
D = \(\frac{2x-3}{x-1}\)
\(D=\frac{2x-3}{x-1}=\frac{2x-2-1}{x-1}=\frac{2.\left(x-1\right)-1}{x-1}=\frac{2.\left(x-1\right)}{x-1}-\frac{1}{x-1}=2-\frac{1}{x-1}\)
Để D nguyên thì \(\frac{1}{x-1}\)nguyên
=> 1 chia hết cho x - 1
=> \(x-1\inƯ\left(1\right)\)
=> \(x-1\in\left\{1;-1\right\}\)
=> \(x\in\left\{2;0\right\}\)
TIm x thuoc Z de cac ps sau co gia tri la so nguyen :
D = \(\frac{2x-3}{x-1}\)
\(D=\frac{2x-3}{x-1}=\frac{2}{1}.\frac{x-1-2}{x-1}=2.1-\frac{2}{x-1}\)
=> \(x-1\inƯ\left(2\right)\)
* x - 1 = 1 => x = 0
* x - 1= 2=> x = 3
* x - 1 = -1 => x = 0
* x - 1 = -2 => x = -1
đúng ko nhỉ?
tim gia tri cua x thuoc Z de cac bieu thuc sau co gia tri nguyen :a) \(\frac{\sqrt{x}+5}{\sqrt{x}+1}\)
b) \(\frac{\sqrt{x}+2}{\sqrt{x}-2}\)
1)cho phan so A=\(\frac{n+1}{n-2}\)
a tim n thuoc Z de A co gia tri nguyen
b tim n thuoc Z de A co gia tri lon nhat
\(\frac{n+1}{n-2}=\frac{\left(n-2\right)+3}{n-2}=\frac{n-2}{n-2}+\frac{3}{n-2}=1+\frac{3}{n-2}\)
Để \(\frac{3}{n-2}\in Z\) <=> 3 ⋮ n - 2 => n - 2 ∈ Ư ( 3 ) = { - 3 ; - 1 ; 1 ; 3 }
=> n ∈ { - 1 ; 1 ; 3 ; 5 }
1, tim x thuoc Z de cho cac phan so sau la so nguyen
A, x+1 / 3
B, 17 / x -1
2, tim x thuoc Z de cho cac phan so sau dong thoi co gia tri nguyen
C, -12 / x
D, 15 / x -2
E, 8 / x +1
Bài 1:
a: Để A là số nguyên thì \(x+1⋮3\)
=>x=3k-1, với k là số nguyên
b; Để B là số nguyên thì \(x-1\in\left\{1;-1;17;-17\right\}\)
hay \(x\in\left\{2;0;18;-16\right\}\)