Square of 4 (a-b) - square of 16 (a + b) = (factorize, please)

Square of 4 (a-b) - square of 16 (a + b) = (factorize, please)

4（a-b）²-16（a+b）

Factorization 3x ^ 2 + 12xy + 11y ^ 2 using discriminant

If y is regarded as a constant, then
△=（12y）²-4*3*11y²
=12y²
Substituting the root formula to get X1 and X2, then the original formula = (x-x1) (x-x2)

The second order partial derivative of binary function
How do two mixed partial derivatives of the second order partial derivatives of a function of two variables derive? For example, the second-order partial derivatives of X and y are derived twice respectively. How do the mixed partial derivatives derive? First, the partial derivatives of X, then the partial derivatives of Y, and then the multiplication? Then why are the two mixed partial derivatives not necessarily equal?

Generally speaking, the partial derivative can be calculated separately for each independent variable. If fxy or fyx occurs, the partial derivative of X is calculated first, and then the function after X derivative is regarded as the function of Y, and then y is calculated, and vice versa
It is best to use examples:
F（x,y）=x^2y+xy^2
Fx=2xy+y^2
Fxy=2x+2y
Fxx=2y
Fy=2xy+x^2
Fxy=2x+2y
Fyy=2x
Fxx+Fyy=2x+2y
.
Add the combinations above

Junior high school mathematics problem solving known ∣ 2a-b ∣ and (B-1) square is opposite to each other, find the value of (a + b) cube

∣2a-b∣≥0,(b-1)^2≥0
∣ 2a-b ∣ and (B-1) ^ 2 are opposite numbers
So: ∣ 2a-b ∣ = 0, (B-1) ^ 2 = 0
b=1,a=b/2=1/2
（a＋b)^3
=(1+1/2)^3
=(3/2)^3
=27/8
=6 and 3 / 4

88888 with addition, subtraction, multiplication, division and bracket composition 2005 that math master to next······

88*(8+8+8)-8-88-88/8=2005

If we know that the image of the first-order function y = 3x + 2B intersects with the image of the first-order function y = - 4x-1 / 2A at a point on the y-axis, then 3A: 2B=___

The linear function y = 3x + 2B, when x = 0, y = 2B, the intersection coordinates of the function and Y axis are (0,2b)
The linear function y = - 4x-1 / 2a, when x = 0, y = - 1 / 2a, the intersection coordinates of function and Y axis are (0, - 1 / 2a)
If two linear functions intersect at the same point on the y-axis, then:
-1/2a=2b
a=-4b
3a=3×(-4b)=-12b
3a：2b=-12b：2b=-6

There is a circular fountain in the middle of the street, with a diameter of 12 meters. There is a 3 meter wide cement road around the fountain. How many square meters does the cement road cover?

Inner radius 12 △ 2 = 6M
Outer radius 6 + 3 = 9m
Area 3.14 × (9 × 9-6 × 6)
=3.14×45
=141.3 square meters

3.3.8.8 3.3.7.7 10.10.4.4 8.8.7.10 how to calculate 24 points?
Every topic should be done (the formula should also be given examples) it's best to use the equation to calculate!

(3-8 / 3) * 8 = 24 (3 + 3 / 7) * 7 = 24 (10 * 10-4) / 4 = 24 the last one is unknown

The circular curvature of the equation x ^ 2 + y ^ 2-4x = 0 is

x^2+y^2-4x=0
(x-2)^2+y^2=4
The radius of curvature is the radius of the circle: r = 2
The curvature of a circle is equal to the reciprocal of its radius, that is, k = 1 / 2

The volume of a bucket is 24 cubic decimeters, the bottom area is 7.5 square decimeters, and there is a hole 0.7 decimeters away from the bucket mouth. Now the bucket can hold water at most______ Kg. (1 kg per cubic decimeter of water)

Now this bucket can hold water: 1 × (24-7.5 × 0.7), = 1 × (24-5.25), = 18.75 (kg); answer: now this bucket can hold water up to 18.75 kg. So the answer is: 18.75