Fractional equation No, why is the fractional equation not solved?

Just write (1), and it's easy to understand the solution: (!= means not equal to) solution: known by x!=1 and -1

Multiply both sides by (1-x) (1+x) to simplify:

2(1+x)+(1-x)(1+x)=x(1-x) solution: x=-3

When x=-3, there is no rooting, which is true.

There are two cases in which a fractional equation is unsolved

One is that after the fractional equation is converted into an integral equation, the integral equation has no solution.

One is that after the fractional equation is converted into an integral equation, the integral equation has a solution, but this solution makes the denominator of the fractional equation 0, which is the root increase.

The generation of root enhancement is caused when the first step of solving the fractional equation, "removing the denominator".

According to the principle of homogeneous solution of equations, both sides of the equation are multiplied (or divided) by the same non-0 number, and the resulting equation is the homogeneous equation of the original equation.

If the number multiplied by both sides of the equation is 0, then the obtained equation is not the same solution as the original equation, and the root obtained is the additional root of the original equation, that is, the original fractional equation has no solution.

Note:

1) Pay attention to the denominator when removing the denominator, do not omit to multiply the integer term.

2) The root is the root of the integral equation formed by removing the denominator from the fractional equation, but it is not the root of the original fractional idiot equation.

3) Root increment so that the simplest common denominator is equal to 0.

4) In a fractional equation, if x is the denominator, then x should not be equal to 0.

Bring x=a into the simplest common denominator, and if x=a makes the denominator of the simplest band slam to 0, then a is the root of the original equation. If x=a makes the simplest common denominator not zero, then a is the root of the original equation.

The unsolved fractional equation means that no matter what value is taken, the equality of both sides of the fractional equation cannot be satisfied, and there are two main situations in which the fractional equation is unsolved

1. After the original fractional equation is multiplied by the simplest common denominator on both sides of the equal sign at the same time to reduce it to an equation equation, the equation has no solution;

2. After the fractional equation is converted into an equation equation, the integral equation has a solution, but this solution makes the denominator of the original fractional equation 0, and this solution is called the root addition of the fractional equation.

If the property of non-solution of fractional equations can be correctly applied in the actual problem solving, it will help to effectively improve the efficiency of problem solving, understand the problem more clearly, and solve other problems.

When solving fractional equations:

Removing the denominator so that the solution of the integer equation obtained after the loss is known may make the denominator in the original equation zero, so the solution of the integer equation should be substituted into the simplest common denominator, and if the value of the simplest common denominator is not zero, it is the solution of the equation.

If the simplest common denominator is equal to 0, the root is an incremental root. Otherwise, this root is the root of the hollow branch primitive equation. If the solved roots are all incremental roots, then there is no solution to the original equation.

This equation is a problem for solving fractional equations! The steps of solving the fractional equation are: find the simplest common factor (denominator) and convert it into a one-dimensional equation, and then calculate it according to the brackets, shift the terms, merge the similar terms, and convert the coefficient to 1

Hope, thank you!

Left and right multiplication x 800-800 (5 4) = 40x because 800 (5 4) = 800 * 4 5 = 640 so the original formula 160 = 40x

Left and right divide by 40 4=x

So the answer is x=4

(1) The specified period is x days, 2 x + x (x + 3) = 1

The solution yields x=62)2 x+2(x-2-2) x=1

x=63).

Suppose that the number of days required for Team B to complete the project alone is x days, and it takes 2x 3 (two-thirds x) days for Team A.

10+30) (2x 3)+30 x=1 to get x=90, then team A needs 2x 3=60 days.

The second question is how many days it takes for teams A and B to cooperate to complete this project: 1 (1 60 + 1 90) = 36 days.

The total construction cost is: 36 (10,000 yuan.

So it's not enough, you need to add: 10,000 yuan.

Solution: (x+a) (x-2)=-1

Multiply (x 2) on both sides of the equation

x＋a＝2－x

2x＝2－a

x＝[（2－a）／2]

The root of the equation x+a x-2=-1 about x is a positive number x 0, i.e. [(2 a) 2] 0

2－a＞0a＞－2

A 2 test: When x 2, x 2 0 fractional equation has no solution x≠2

i.e. (2 a) 2≠2

2－a≠4a≠－2

The value range of a is a 2 and a ≠ 2

(x+a) (x-2)+(x-2) (x-2)=0 (x-2)(2x+a-2)=0 x=2 or x=(2-a) 2>0 a<0 Hope it helps.

This is not a fractional equation, it's a quadratic equation.

Multiply both sides of the equation by 20 to form an integer to get 5(9-y)-4y=20

The solution is y= 5 3

Set the first year x yuan, the second year x + 500 yuan.

The number of rooms is the same. Multiply both sides by x(x+500).

x=8000

x+500=8500

So 8,000 yuan for the first year and 8,500 yuan for the second year.

Answer: This is a conclusion based on the nature of the identity.

In order for the left and right formulas to be equal, the coefficients of the same terms to which they correspond must be equal.