It is known that a + B = 6, the negative power of (AB) = - 1 / 7, Find the value of A-B / 3AB × (A & # 178; - B & # 178; / A & # 178; + 2Ab + B & # 178;) to the negative power It's a process!

It is known that a + B = 6, the negative power of (AB) = - 1 / 7, Find the value of A-B / 3AB × (A & # 178; - B & # 178; / A & # 178; + 2Ab + B & # 178;) to the negative power It's a process!

A-B / 3AB × (A & # 178; - B & # 178; / A & # 178; + 2Ab + B & # 178;) negative power
=(a-b)/3ab×(a+b)²/(a+b)(a-b)
=(a+b)/3ab
=The (- 1) power of (a + b) × (AB) / 3
=6×(-1/7)/3
=-2/7

If x * 2-x-1 = 0, then - x * 3 + 2x * 2 + 2007=____________ .

2008
-X*3+2X*2+2007=-X*3+X*2+x+x^2-x-1+2008=2008

In order to solve the travel problem with linear equation of one variable, we should further master the basic steps of solving practical problems with linear equation of one variable: (), (), (),
（ ）,（ ）,（ ）,

(1) Examination: read the title, examine the meaning of the title, make clear which are, which are, and the relationship between them
(2) Set element: it is to set the unknown number, according to the meaning of the topic, choose the appropriate. And express it with. Set element is divided into direct set element and indirect set element
(3) Lie equation: according to the relation given in the title, list the quadratic equation of one variable which accords with the meaning of the title
(4) Solving the equation: finding the solution of the listed equation
(5) Check the root: check whether it conforms to the meaning of the question
(6) Write the answer

What is 26.9 divided by 2?

13.45

Every two people who attended a party shook hands once, and all of them shook hands 10 times______ People go to the party

According to the equation, X (x-1) 2 = 10, the solution is X1 = 5, X2 = - 4. A: there are 5 people attending the party. So the answer is: 5

What's 5 out of 26 times 13?

5 / 338

Through calculation, determine whether the number in braces after the following equation is the solution of the corresponding equation 3x + 2 = x {- 1,1}; 3x + 5 = 4x-2 {3,7}

3x+2=x {-1,1} ；
3x-x=-2
2x=-2
∴x=-1
3x+5=4x-2 {3,7}
3x-4x=-2-5
-x=-7
∴x=7

How to calculate 21.5 × 1.9 + 2.15 × 81,

21.5*1.9=2.15*19
Original formula = 2.15 * (19 + 81) = 2.15 * 100 = 215

Given the triangle ABC, a = 5, B = 3, C = 120 degrees, find the value of sina

According to the cosine theorem:
cosc=（a*a+b*b-c*c)/(2ab)
-0.5=(34-c*c)/30
c=7
According to the sine theorem:
a/sinA=c/sinc
sina=(a/c)sinc
=(5 / 7) * (radical 3) / 2
=(5 / 14) * (radical 3)

Try to compare the size of 2008 × 20072007 and 2007 × 20082008
Answer quickly ~ ~ ~ hurry!

=
2008×20072007=2008×2007×10001
2007×20082008=2007×2008×10001