Fill a 15 cm square glass fish tank with water, then pour the water into a 20 cm long, 15 cm wide and 12 cm high rectangular tank

Fill a 15 cm square glass fish tank with water, then pour the water into a 20 cm long, 15 cm wide and 12 cm high rectangular tank

15 * 15 * 15 = 3375 (cm3)
3375 divided by 15 divided by 20 = 11.25 (CM)

A cuboid tank 50 cm long, 40 cm wide and 30 cm deep is filled with water. Put a cube 8 cm long in it to find the overflow water
Formula. Thinking

It is not clear whether the cube completely enters into the water. If it completely invades into the water, then the beneficial water volume is the cube volume, that is, 8 ^ 3 = 512, the density of water is 1g / cm ^ 3, then the overflow water is 512g. If it does not completely invade, it is between 0.512

A cuboid tank 50 cm long, 40 cm wide and 30 cm deep is filled with water. If you put a cube stone with an edge length of 8 cm in it, the water will come out
A cuboid water tank, 50 cm long, 40 cm wide and 30 cm deep, is full of water. If a cube stone with an edge length of 8 cm is put in it, how much will the water benefit?
Come on, the teacher will hand it in tomorrow,

8 cube = 512cm3 50 40 30 are traps

Let two-dimensional random variables (x, y) obey the field G: x ^ 2 + y ^ 2

Draw a graph and integrate with X to get FY (y). Draw a horizontal line to intersect at 2 points, whose abscissa are - √ R ^ 2-y ^ 2, √ R ^ 2-y ^ 2, that is, the upper and lower limits of integration. For y integration, you can get FX (x). Similarly, draw a vertical line to intersect at 2 points, whose ordinates are - √ R ^ 2-x ^ 2, √ R ^ 2-x ^ 2, that is, the upper and lower limits of integration

Using MATLAB to find all solutions of equation 5 * (X. ^ 2) * sin (x) - exp (- x) in interval [0,10]

The following is only for reference, if you have a better way, welcome to exchange
1. If the solution of the equation is selected manually, it can be written as follows
fx=inline('5*x.^2.*sin(x)-exp(-x)');
x0=fsolve(fx,0:10)
y=subs(fx,'x',x0)
From the result of x0, we can know that the equation has four solutions in [0,10]
2. All solutions of the equation in [0,10] can be displayed automatically
fx=inline('5*x.^2.*sin(x)-exp(-x)');
x0=fsolve(fx,0:10);
j=2;a(1)=x0(1);
for i=1:9
if (abs(x0(i+1)-x0(i)>10^(-5)))
a(j)=x0(i+1);
j=j+1;
end
end
Four solutions of a% equation in [0,10]
The corresponding value of y = subs (FX, 'x', a)% equation at a is approximately 0
Results of operation:
a =
5.017630305147549e-001 3.140715698599913e+000 6.283194767636995e+000 9.424777779067769e+000
y =
4.371324557883582e-008 -8.416878305439468e-015 -1.502465686586962e-014 3.462214239260963e-013

How much is 8 yuan and 3 Jiao

8.3 yuan

A triangle and a parallelogram have the same base and height. The area of the parallelogram is 0.19 square decimeter larger than that of the triangle
What's the total area

The area of a parallelogram is twice that of a triangle
Because the area of parallelogram is 0.19 square decimeter larger than that of triangle
So the area of the triangle is 0.19 bisection decimeter
The area of a parallelogram is 0.38 square decimeter
The sum of area is 0.19 + 0.38 = 0.57 square decimeter

In quadratic function, the vertex is (h, K). H = 4ac-b ^ 2 / 4A. But x in vertex formula is - B / 2A?

You're wrong, (4ac-b & # 178;) / 4A represents the Y coordinate, that is, K, is the height of the vertex of the parabola. And - B / 2a is the X coordinate of the vertex, that is, the H point

If the square + X-1 of cube-10x of polynomial 3x and the square + 3 of cube + 2mx-4x of polynomial 3x are added without quadratic term, then M =?

The cube of 3x - the square of 10x + X-1 + the cube of 3x + the square of 2mx - the square of 4x + 3
=Cube of 6x - (10-2m + 4) square of X + 2
Because there is no quadratic term
So 10-2m + 4 = 0
2m=10+4
m=7

If the width of a rectangle is reduced by 3 cm and the width remains unchanged, the area will be reduced by 12 square cm. If the width is reduced by 2 cm and the length remains unchanged, the area will be reduced by 20 square cm
Square centimeter, how much square centimeter is the original area of this rectangle? How can the third grade children explain and understand it

If the length decreases by 3cm and the width remains unchanged, the area decreases by 3 * width = 12, so the width is 4cm. Similarly, the length is 20 / 2 = 10cm