C©u 4: Chøng minh ph¬ng tr×nh: 2x2 – 4y = 10 kh«ng cã nghiÖm nguyªn C©u 4: Chøng minh ph¬ng tr×nh: 2x2 – 4y = 10 kh«ng cã nghiÖm nguyªn C©u 5: a, T×m nghiÖm ∈ Z cña PT: xy – 4x = 35 – 5y b, T×m nghiÖm ∈ Z cña PT: x2 + x + = y2 C©u 5: a, T×m x,y,x ∈ Z biÕt: x2 + 2y2 + z2 - 2xy – 2y + 2z +2 = b, T×m nghiÖm nguyªn cña PT: 6x + 15y + 10z = T×m nghiÖm nguyªn d¬ng cña PT: x y z + + = 2x + y + z y + x + z 2z + x + y T×m nghiÖm nguyªn cña PT: x2 = y(y+1)(y+2)(y+3) C©u 4: T×m x, y, z biÕt: x+y–z = y+z-x = z+x-y = xyz C©u 4: a, T×m sè tù nhiªn m, n cho: m2 + n2 = m + n + b, T×m sè nguyªn nghiÖm ®óng: 4x2y = (x2+1)(x2+y2) C©u 6: T×m x, y ∈ N biÕt: 2x + = y2 C©u 6: T×m nghiÖm nguyªn cña PT: xy xz yz + + =3 z y x C©u 4: a,T×m nghiÖm ∈ Z+ cña: 1 + + =2 x y z b, T×m nghiÖm ∈ Z cña: x4 + x2 + = y2 – y C©u 3: T×m nghiÖm nguyªn cña PT: 4x2y = (x2+1)(x2+y2) C©u 4: T×m nghiÖm nguyªn cña PT: x(x2+x+1) = 4y(y+1) C©u 5: T×m nghiÖm nguyªn cña PT: 1 + + =1 x y z C©u 2: T×m nghiÖm nguyªn cña PT: 1+x+x2+x3 = y3 C©u 2: T×m sè nguyªn x, y, z tho¶ m·n: x2 + y2 + z2 < xy + 3y -3 C©u 4: T×m x, y ∈ Z+ : x2 + (x+y)2 = (x+9)2 C©u 4: T×m nghiÖm nguyªn cña PT: a, xy – = x + y b, 3xy + x – y = C©u 4: T×m nghiÖm nguyªn d¬ng cña PT: 2(x+y+z) + y = 3xyz C©u 5: T×m nghiÖm nguyªn cña PT: 5x – 3y = 2xy – 11