Question

[Pham Ngoc Diep]

Bài 5.   Tìm x ∈ Z biết:

          a) (x – 2)(– 4 – x²) > 0

          b) (x² + 2)(x + 3) > 0

          c) (x + 3)(x – 4) > 0. Mik sẽ tick nha

Answer 1

[Nguyễn Hoàng Minh]

\(a,\Leftrightarrow\left(2-x\right)\left(x^2+4\right)>0\Leftrightarrow2-x>0\Leftrightarrow x< 2\\ b,\Leftrightarrow x+3>0\Leftrightarrow x>-3\\ c,\Leftrightarrow\left[{}\begin{matrix}x< -3\\x>4\end{matrix}\right.\)

Answer 2

[Nguyễn Lê Phước Thịnh]

b: \(\Leftrightarrow x+3>0\)

hay x>-3