x/4-1/y=1/2
=> 1/y=x/4-1/2
=> 1/y=x/4-2/4
=>x=2+1;y=4
=>x=3;y=4.
vay x=3;y=4
x/4-1/y=1/2
=> 1/y=x/4-1/2
=> 1/y=x/4-2/4
=>x=2+1;y=4
=>x=3;y=4.
vay x=3;y=4
Tim cac so Nguyên x va y biet :
a) \(\frac{1}{y}+\frac{x}{4}=\frac{1}{2}\) b)\(\frac{5}{x}+\frac{y}{4}=\frac{1}{8}\)
Tim x biet
Bai 1: Tim cap so (x,y) biet: \(\frac{1+3y}{12}=\frac{1+5y}{5x}=\frac{1+7y}{4x}\)
Bai 2; Cho \(\frac{a}{b}\)=\(\frac{b}{c}\)=\(\frac{c}{a}\)va a,b,c khac ; a=2012. tinh b,c
Bai 3: tim cac so x,y,z biet :
\(\frac{y+x+1}{x}\)=\(\frac{x+z+2}{y}\)=\(\frac{x+y-3}{z}\)=\(\frac{1}{x+y+z}\)
Bai 4: Tim x, biet rang:\(\frac{1+2y}{18}=\frac{1+4y}{24}=\frac{1+6y}{6x}\)
giup minh di minh dang rat gap cam on
tim cac so nguyen x va y sao cho
\(\frac{5}{x}\)+\(\frac{y}{4}\)=\(\frac{1}{8}\)
tim cac cap so x,y biet:
\(\frac{x}{2}=\frac{y}{5}\)va x.y =90
\(\frac{3x-y}{x+y}=\frac{3}{4}\)tim\(\frac{x}{y}\)
tim tat ca cac cap so nguyen x,y thoa man;\(\frac{1}{x}\)+\(\frac{1}{y}\)=\(\frac{1}{p}\)trong do p la so nguyen to cho truoc
cau 1: Cho A= \(\frac{100^{2014}+2}{3}-\frac{100^{2015}+17}{9}.\)tong cac cua so cua B=-9A
Cau 2: So sanh A=\(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+........+\frac{1}{100.101}\)voi 1 ta doc A....1
Cau 3 : Cho bon so a,b,c,d sao cho a+b+c+d khac 0 . Biet \(\frac{b+c+d}{a}=\frac{c+d+a}{b}=\frac{d+a+b}{c}=\frac{a+b+c}{d}=k\). Vay k=
Cau 4 : so cac so nguyen am x thoa man \(x^{2015}=\left(-2\right)^{2014}\)
Cau 5; tim x,y,z biet \(\frac{x}{y}=\frac{10}{9},\frac{y}{z}=\frac{3}{4}\)va x-y+z=78
Cau 6: tap hop cac so co ba chu so chia het cho 18 va tong cac chu so ti le voi 1;2;3 la
Cau 7: gia tri cua tong S=1.2+2.3+.....+49.50 la S=
Tim x,y,z biet rang: \(\frac{y+z+1}{x}=\frac{x+z+2}{y}=\frac{x+y-3}{z}=\frac{1}{x+y+z}\)
tim so nguyen duong x,y,z biet:
\(\frac{1}{x}\)+\(\frac{1}{y}\)+\(\frac{1}{z}\)=1
c1: Tap hop cac gia tri nguyen cua x thoa man \(\left(x+\frac{5}{4}\right)\left(x-\frac{19}{7}\right)\)<0
c2: Neu x,y la cac so nguyen thoa man 2xy+4y=6 thi y co the nhan nhung gia tri nam trong tap hop nao
c3: tim 3 so x,y,z biet x+y=8,x+z=10,y+z=12
C4: Gia tri cua x thoa man (x+3)^2=25 va x^3>0 la x=