Known: x + 2Y = 2011, find the value of the algebraic formula {(x ^ + y ^) - (X-Y) ^ + 2x (x + y)} / 2x

Known: x + 2Y = 2011, find the value of the algebraic formula {(x ^ + y ^) - (X-Y) ^ + 2x (x + y)} / 2x

Simplification of the original formula = x + 2Y = 2011

Given that x 1 and x 2 are two of the equations x 2-4x + 2 = 0, we can find: (1) the value of 1 x 1 + 1 x 2; (2) the value of (x 1-x 2) 2

∵x1+x2=4，x1x2=2．（1）1x1+1x2＝x1+x2x1x2＝42=2．（2）（x1-x2）2=（x1+x2）2-4x1x2=42-4×2=8．

When x takes what value, is the algebraic formula 1 / (x2-1) △ 1 / (x2 + 1 + 2x) △ x + 1 / (x2-x) - x + 1 meaningful?

X is not equal to 0, 1, - 1

The greatest common factor of two numbers is 6, the least common multiple is 108, one of which is 12, what is the other number?

The other number is 54

Let a > b > 0 find the minimum value of a ^ 2 + 1 / (AB) + 1 / [a (a-b)]

∵ 1 / (AB) + 1 / [a (a-b)] = 1 / (AB) + 1 / (a ^ 2-AB) = a ^ 2 / [AB (a ^ 2-AB)] ≥ a ^ 2 * [2 / (AB + A ^ 2-AB)] ^ 2 = 4 / A ^ 2. If and only if a = 2B, the equal sign holds a ^ 2 + 1 / (AB) + 1 / [a (a-b)] ≥ a ^ 2 + 4 / A ^ 2 ≥ 4. If and only if a = √ 2, the minimum value of the equal sign holds a ^ 2 + 1 / (AB) + 1 / [a (a-b)] is

It is known that f (x) is an odd function on R, and when x is greater than or equal to 0, f (x) = the square of x-3x, then when x is less than 0, the analytic expression of F (x) is?

hello
F (x) is an odd function on R
So f (- x) = - f (x)
When x is greater than or equal to 0, f (x) = x ^ 2-3x
When X0
So the generation still holds, that is, f (- x) = (- x) ^ 2-3 * (- x) = x ^ 2 + 3x
Because f (- x) = - f (x), x ^ 2 + 3x = - f (x)
That is, f (x) = - x ^ 2-3x
I don't know how to add

410-39 + 61 with simple method

410-39+61
=410—40＋1＋60＋1
=410＋60—40＋1＋1
=430＋2
=432

If you add two fifths of a number to it, you get 1.4

Let this number be X
x+2/5x=1.4
1.4x=1.4
x=1

How about 2x-10.3x

=(2-10.3)x
=-8.3x

How to calculate the simple method of multiplying (42 + 26) by 25

4 by 25 is 17