Question

[nhok_lạnh_lùng]

Ta có: (x+1/99) + (x+2/98) + (x+3/97) = -3. Tìm x? ( / = phần)

Answer 1

[Hoàng Ninh]

\(\left(\frac{x+1}{99}\right)+\left(\frac{x+2}{98}\right)+\left(\frac{x+3}{97}\right)=-3\)

\(\Rightarrow\left(\frac{x+1}{99}+1\right)+\left(\frac{x+2}{98}+1\right)+\left(\frac{x+3}{97}+1\right)=-3\)

\(\Rightarrow\frac{x+100}{99}+\frac{x+100}{98}+\frac{x+100}{97}=0\)

\(\Rightarrow\left(x+100\right)\left(\frac{1}{99}+\frac{1}{98}+\frac{1}{97}\right)=0\)

Vì \(\frac{1}{99}+\frac{1}{98}+\frac{1}{97}\approx0\)nên \(x+100=0\)

\(\Rightarrow x=-100\)

Vậy x = -100

Answer 2

[Phùng Minh Quân]

Ta có : 

\(\frac{x+1}{99}+\frac{x+2}{98}+\frac{x+3}{97}=-3\)

\(\Leftrightarrow\)\(\left(\frac{x+1}{99}+1\right)+\left(\frac{x+2}{98}+1\right)+\left(\frac{x+3}{97}+1\right)=-3+3\)

\(\Leftrightarrow\)\(\frac{x+100}{99}+\frac{x+100}{98}+\frac{x+100}{97}=0\)

\(\Leftrightarrow\)\(\left(x+100\right)\left(\frac{1}{99}+\frac{1}{98}+\frac{1}{97}\right)=0\)

Vì \(\frac{1}{99}+\frac{1}{98}+\frac{1}{97}\ne0\)

\(\Rightarrow\)\(x+100=0\)

\(\Rightarrow\)\(x=-100\)

Vậy \(x=-100\)

Chúc bạn học tốt ~