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Dy / DX = 2Y (3-y) Lim "x →∞" why is y = 3 y(4)=1 Why can we conclude that the limit is 3 instead of 0 when we don't understand the differential equation?
Because from dy / DX = 2Y (3-y)
When y
Homogeneous equation solution: dy / DX = f (Y / x), let u = Y / x, next step y = UX (dy / DX) = u + X (DU / DX) how to come ah, will be more detailed thank you!
Take both sides of the product of y = u and X as derivatives, y derivative is dy / DX, and UX guideline uses the rule of leading followed by no leading + leading followed by no leading = u'x + UX '= (DU / DX) x + U
Find the rules 1, 15, 3, 13, 5, 11, (), ()
Find the rules 1, 15, 3, 13, 5, 11, (), ()
7 and 9
What are the factors of all nonzero natural numbers
Is 1, 1 is the factor of all nonzero natural numbers
I want to know the mathematical definitions of natural numbers, integers and rational numbers
You don't need to talk about integers
Natural numbers include 0 and all positive integers
Integers and fractions are called rational numbers
1. A farmer went to the street to sell eggs. The first one bought more than half of all the eggs, the second one bought more than half of the remaining eggs, and the third one bought more than half of the remaining eggs. At this time, there were just 10 eggs left in the basket. How many eggs did the farmer take to sell in the street?
2. It's interesting to add, subtract, multiply and divide a number. The result is 81. Please guess what the number is?
3. Birds come and fall on the treetops. One bird falls on each tree, but no one can find it. Two birds fall on each tree, but no one can find it. Guess how many trees and how many birds are there?
1. If there are 10 eggs left, the third person will buy 10 + 1 + 1 = 12; the second person will buy (12-1) * 2 + 1 + 1 = 24; then the first person will buy (24-1) * 2 + 1 + 1 = 48; the total is 48 + 24 + 12 + 10 = 94
2. According to the multiplication table, 9 times 9 equals 81, so this number must be less than 9, that is, a number between 1 and 8. Then check one by one to see that this number is equal to 8
3. From the title, we can know that there is one tree less than birds, and there is one tree twice as many as birds
Three continuous natural numbers, from small to large, are multiples of 7, 11 and 13. What is the minimum sum of these three natural numbers?
5555555555555555555555555555555
Let the three numbers be 7a, 11b and 13C
Because they are continuous natural numbers, so
7a+1＝11b＝13c-1
Find the integer solution of the indefinite equation
a＝113、b＝72、c＝61
7a＝791,11b＝792,13c＝793
Is the square root of (x + 1) quadratic
The square root of (x + 1) is √ x ^ 2 + 1
∵x^2+1＞0
So the original is a quadratic radical
There is a batch of goods in the warehouse. 15 tons were transported in the first day, and 8 tons more in the second day than in the first day. 1425 tons of the total weight of this batch of goods are left. How many tons of this batch of goods are there?
A: there are 200 tons of this batch of goods
5.3 * 2.7 + 5.7 * 2.7-2.73.8 + 16.2 / (2.7 * 0.8) can be calculated simply, but it should be calculated simply
5.3 * 2.7 + 5.7 * 2.7-2.7 and 3.8 + 16.2 / (2.7 * 0.8) can be calculated simply
5.3*2.7+5.7*2.7-2.7=2.7*（5.3+5.7-1）=2.7*10=27
3.8+16.2/(2.7*0.8)=3.8+(16.2/2.7)/0.8=3.8+6/0.8=3.8+7.5=11.3
RELATED INFORMATIONS
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