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On line Solution of Monovariate Equation：
Input any unary equation directly, and then click the "Next" button to obtain the solution of the equation.
It supports equations that contain mathematical functions.
Input any unary equation directly, and then click the "Next" button to obtain the solution of the equation.
It supports equations that contain mathematical functions.
Current location：Equations > Monovariate Equation > The history of univariate equation calculation > Answer
Overview: 1 questions will be solved this time.Among them
☆1 equations
[ 1/1 Equation]
Work: Find the solution of equation 800 = 400/1+r+300/(1+r)2+300/(1+r)3 .
Question type: Equation
Solution:Original question:
| 800 | = | 400 | ÷ | 1 | + | r | + | 300 | ÷ | ( | 1 | + | r | ) | × | 2 | + | 300 | ÷ | ( | 1 | + | r | ) | × | 3 |
| Multiply both sides of the equation by: | ( | 1 | + | r | ) |
| 800 | ( | 1 | + | r | ) | = | 400 | ÷ | 1 | × | ( | 1 | + | r | ) | + | r | ( | 1 | + | r | ) | + | 300 | × | 2 | + | 300 | × | 3 |
| 800 | × | 1 | + | 800 | r | = | 400 | ÷ | 1 | × | ( | 1 | + | r | ) | + | r | ( | 1 | + | r | ) | + | 300 | × | 2 | + | 300 | × | 3 |
| 800 | × | 1 | + | 800 | r | = | 400 | ÷ | 1 | × | 1 | + | 400 | ÷ | 1 | × | r | + | r | ( | 1 | + | r | ) | + | 300 | × | 2 | + | 300 | × | 3 |
| 800 | + | 800 | r | = | 400 | + | 400 | r | + | r | ( | 1 | + | r | ) | + | 600 | + | 900 |
| 800 | + | 800 | r | = | 1900 | + | 400 | r | + | r | ( | 1 | + | r | ) |
| 800 | + | 800 | r | = | 1900 | + | 400 | r | + | r | × | 1 | + | r | r |
| 800 | + | 800 | r | = | 1900 | + | 401 | r | + | r | r |
r≈2.776209 , keep 6 decimal places
There are 1 solution(s).
解一元一次方程的详细方法请参阅：《一元一次方程的解法》