Overview: 1 questions will be solved this time.Among them
           ☆1 inequalities

[ 1/1Inequality]
    Assignment:Find the solution set of inequality (-4x^2+100x+1200)/(x^2-400) <0 .
    Question type: Inequality
    Solution:
    The inequality can be reduced to 1 inequality：
         ( -4 * x ^ 2 + 100 * x + 1200 ) / ( x ^ 2 - 400 ) <0         (1)
        From the definition field of divisor
         x ^ 2 - 400 ≠ 0        (2 )

---

    From inequality(1)：
         x < -20 或  -8.860009 < x < 20 或  x ＞ 33.860009
    From inequality(2)：
         x < -20 或  -20 < x < 20 或  x ＞ 20

---

    From inequalities (1) and (2)
         x < -20 或  -8.860009 < x < 20 或  x ＞ 33.860009    (3)

---

    The final solution set is :
         x < -20 或  -8.860009 < x < 20 或  x ＞ 33.860009

Your problem has not been solved here? Please take a look at the  hot problems ！