3 so x;y;z thoa man 2x=3y;5y=7z va3x-7y+5z=-30
cm trong 3 so x,y,z ton tai 1 so bang tong 2 so con lai biet
x.(y-z)^2+y.(x-z)^2+z.(x-y)^2-x^3-y^3-z^3+4xyz=0
1.so nghiem cua da thuc x4-x3+x2x la
2.viet so 1993-199 duoi dang tich cua 3 so tu nhien lien tiep so be nhat trong 3 so tu nhien do la
3.tap hop cac gia tri cua x\(\ne\)0 thoa man x3-4x=0 la S(...)
Nhung so nao trong cac so:-4;-3;-2;-1;0;1;2;3;4 la gia tri cua so nguyen x thoa man :x.(4+x)=-3
ban dang lam bai nay dung ko minh dang lam ne
1.Tim cac chu so x va y de so 1x8y2 chia het cho 36
2.tim cac gia tri nguyen cua n de phan so A=3.n+2/n-1 co gia tri la so nguyen
3.tim cac chu so x y thoa man
(x-2)^2.(x-3)^2=4
4.tim so tu nhien x biet
(x-5):3/100=20.x/100 +5
tim x
a, 2^x + 2^x+3 = 144 ( x+3 la so mu )
b,3^2x + 2 = 9^x+3 ( 2x va x+3 la so mu )
a. ta có : 2x + 2x+3 = 144=
2x + 2xnhân 23=144
2x(1 + 23) =144
2x nhân 9 =144
2x = 144 : 9
2x = 16
2x = 24
suy ra : x = 4
tim so nguyen x de phan so sau la so nguyen x+3/x-2
Để \(\frac{x+3}{x-2}\) nguyên thì \(x+3\) \(⋮\) \(x-2\)
\(x+3⋮x-2\)
\(\Rightarrow x-2+5⋮x-2\)
\(x-2⋮x-2\)
\(\Rightarrow5⋮x-2\)
\(\Rightarrow x-2\inƯ\left(5\right)\)
\(x\in Z\Rightarrow x-2\in Z\)
\(\Rightarrow x-2\in\left\{-1;1;-5;5\right\}\)
\(\Rightarrow x\in\left\{1;3;-3;7\right\}\)
so tu nhien x thoa man dieu kien 0.(x-3)=0.so x bang
(A)0
(B)3
(C)so tu nhien bat ki
(D) so tu nhien bat ki lon hon hoac bang 3
tim tat ca cac so nguyen duong x,y sao cho cac so x2+3.y va y2+3.x deu la so chinh phuong cua 1 so
1:x la so nguyen
2:x la so nguyen
1:(x-1) la so nguyen
-3:x(x-2) la 1 so nguyen
1 tim cac so nguyen x,y biet x/7=6/21 -5/y=20/28 1/2=x/12 x/8=-28/32 3/y=12/24 3/4=15/y 2 viet 3 phan so bang phan so -10/15