Question 5: The denominator can be multiplied by the root number 2 plus the root number 3 minus the root number 5.

Question 6: According to the condition that the root sign is established, the absolute value can be removed. Then we can get the value of a.

Question 7: It is easy to know that x=9 by considering the condition of the root sign, and then believe that you can solve it well.

Question 8: 3 minus 2 can be transformed into a complete square, which can be simplified according to this idea.

The second picture:

Question 2: According to the equation about X, if we know that X is definitely not 0, we can divide it by X on both sides to get the value of X- 1/X, and X3- 1/x3 can be converted into the formula about X-1/X.

Question 3: First, decompose the denominators of the four formulas. Then each equation is divided into two equations for subtraction.

Fourth question: In general, most of us use the difference method. But this problem should be divided into two formulas to compare the size. If it is greater than 1, the numerator is greater than the denominator. Otherwise, the situation is just the opposite.

Question 5: I haven't done it yet-