Overview: 4 questions will be solved this time.Among them
           ☆1 inequalities
           ☆3 equations

[ 1/4 Equation]
    Work: Find the solution of equation x^2 = 4 .
    Question type: Equation
    Solution:
    After the equation is converted into a general formula, it is converted into:
    ( x + 2 )( x - 2 )=0
    From
        x + 2 = 0
        x - 2 = 0
    it is concluded that:：
        x₁=-2
        x₂=2    
    There are 2 solution(s).

解一元二次方程的详细方法请参阅：《一元二次方程的解法》
[ 2/4Inequality]
    Assignment:Find the solution set of inequality x^2+x >0 .
    Question type: Inequality
    Solution:
    The inequality can be reduced to 1 inequality：
         x ^ 2 + x >0         (1)

---

    From inequality(1)：
         x < -1 或  x ＞ 0

---

    The final solution set is :
         x < -1 或  x ＞ 0
[ 3/4 Equation]
    Work: Find the solution of equation e^x = 1 .
    Question type: Equation
    Solution:
    the solutions is:
        x=0    
    There are 1 solution(s).

解方程的详细方法请参阅：《方程的解法》
[ 4/4 Equation]
    Work: Find the solution of equation x^3-10*x = 9 .
    Question type: Equation
    Solution:
    After the equation is converted into a general formula, there is a common factor:
    ( x + 1 )
    From
        x + 1 = 0
    it is concluded that:：

x1=-1

    Solutions that cannot be obtained by factorization:
        x₂≈-2.541381 , keep 6 decimal places
        x₃≈3.541381 , keep 6 decimal places    
    There are 3 solution(s).

解程的详细方法请参阅：《方程的解法》

Your problem has not been solved here? Please go to the Hot Problems section！