tim x biet (x^2-1)(x^2-3)(x^2-5)(x^2-7)<=0
tim x biet :3/[x+2][x+5]+5[x+5][x+10]+7/[x+10][x+15]=x/[x+12][x+17]
tim x biet 2^(x-1) +5^(x-2) =7/12
tim hai so x;y biet: x:2=y:(-5) va x-y = -7
Tim x,y,z biet:
(2|x|+5)/3=(3|y|-1)/5=(3-z)/7 va 2|x|+7|y|+3z=-14
Tim hai so x va y ,biet :x÷2=y÷(-5) va x-y=-7
tim x biet
x-3/x+5=5/7
tim x biet
3/(x+2).(x+5) + 5/(x+5).(x+10) + 7/(x+10).(x+17) = x/(x+2).(x+17)
Với x thuộc tập hợp A = -2;-5;-10;-17
a, Tim x biet:/x-2/+/3-2x/=2x+1
b, Tim x,y thuoc Z biet:xy+2x-y=5
c, tim x,y,z, biet :2x=3y;4y=5zva 4x-3y+5z=7