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Solving a mathematics problem in grade two of junior high school In a village, m HA is planted, and the total yield of corn is n kg; the rice planting area is p ha more than the corn planting area, and the total yield of rice is 2 times more than that of corn. Q kg is used to write the formula of unit area yield of corn and rice [unit; kg / HA]. If the denominators of the two formulas are different, the two formulas are divided
A school canteen stores 45 tons of coal. After five days, due to the improvement of the equipment, the average daily coal consumption is reduced to half of the original, and the result is how many days. How many tons of coal are the average daily coal consumption after the improvement of the equipment?
As a result, how many 10 days, typing more than a word, is the result of burning 10 days
Set to X
5+(45-5*2x)/x-45/2x=10
90-20x-45=10x
X = 1.5 (ton)
After improving the equipment, the average daily coal consumption is 1.5 tons
Proof of the formula of projective theorem for dihedral angle
Projective theorem. There is a simple formula. It seems to be. Projective area / original area = dihedral angle. Generally speaking, what can be solved by projective theorem can be solved by system building method. Projective theorem is suitable for children with fast brain rotation
The complex function f (z) = u + IV is an analytic function, U-V = x ^ 3 + 3x ^ 2-3xy ^ 2-y ^ 3, find U
First of all, you have the wrong title. U-V is not a harmonic function
It should be U-V = x ^ 3 + 3x ^ 2y-3xy ^ 2-y ^ 3
Let g = (1 + I) f, then G = (U-V) + I (U + V). First, find g and express X and y with the conjugate of Z and Z. find the real part of U-V = (1-I) Z ^ 3. So g = (1-I) Z ^ 3. So f = - iz ^ 3. So u = 3x ^ 2y-y ^ 3
The following four exponential functions are given: y = (1 / 2) ^ x, y = 2 ^ x, y = (1 / 3) ^ x, y = 3 ^ X. if y = (1 / 2) ^ X1 = 2 ^ x2 = (1 / 3) ^ X3 = 3 ^ X4. = 3 / 2,
Try to arrange x1, X2, X3, X4 in the order of big to small
Red is a case 0 & lt; & nbsp; Y & lt; 1 & nbsp;, X2 & lt; X4 & lt; X3 & lt; x1
Blue is a case Y & gt; 1, & nbsp; X1 & lt; X3 & lt; X4 & gt; x2
And when y = 1, X1 = x2 = X3 = X4
A simplest fraction, whose numerator is reduced by three times and denominator is expanded by five times, can be reduced to & nbsp; 27___ ．
27 × 5 × 3 = 307, answer: a simplest fraction, its numerator shrinks 3 times, denominator expands 5 times, can be about 27, the original fraction is 307; so the answer is: 307
Find the general solution of the differential equation y "- 2Y '+ 2Y = 0
The characteristic equation is R ^ 2-2r + 2 = 0, R1 = 1 + I, R2 = 1-i
So the solution of the equation is: y = e ^ x * (C1 * cosx + C2 * SiNx)
Find the rules and fill them in
1,8 ,27,【 】,125,【 】
Square of 2-1 = 3, square of 3-2 = 5, square of 7-6 = 13, square of 22-21 = []
1,8,27,64,125,216,
forty-three
What numbers do the letters in this multiplication formula represent
I'd appreciate it if you could tell me how you came up with the answer
A must be 1, or multiply by 9 to get five digits. Therefore, D is a number multiplied by 9 to get 1 at the end, and d = 9
If a = 1, B is not 1, then it must be 0, or it must have five digits. If C and 9 are multiplied by D and 9 times the carry 8, and the mantissa is 0, then C = 8. Therefore, a = 1, B = 0, C = 8, D = 9
In the rectangular coordinate system, a (1,0), B (0,3), C (4,0), D (0,2), AB and CD intersect at point P, find ∠ APC
Translate the line CD so that point d coincides with point B, then the intersection e (6,0) of CD and X axis
The calculated value is ∠ Abe = ∠ APC
In the triangle Abe, ab = radical 10, AE = 5, be = 3 * radical 5
Cos ∠ Abe = (radical 2) / 2 obtained from cosine theorem
So the angle is 45 degrees
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