The minimum value of the function y = X-1 / 3 + X (x > 3) is_______

The minimum value of the function y = X-1 / 3 + X (x > 3) is_______

Derivation of y = [(x-3) - (x + 1)] / (x-3) ^ 2
=-4/(x-3)^2

Finding the minimum value of function y = 1 / 3 x (x > 3)

Let x > - 1, find the maximum value of the function y = (x ^ 2 + 7x + 10) / (x + 1), if x and y are positive numbers, then the minimum value of (x + 1 / 2Y) ^ 2 + (y + 1 / 2x) ^ 2?

(x ^ 2 + 7x + 10) / (x + 1) = 5 + (x + 1) + [4 / (x + 1)] ≥ 5 + 2 √ [(x + 1) * 4 / (x + 1)] = 9 minimum 9 (x + 1 / 2Y) ^ 2 + (y + 1 / 2x) ^ 2 = x ^ 2 + (1 / 4x ^ 2) + (x / y) + (Y / x) + y ^ 2 + (1 / 4Y ^ 2) ≥ 2 * [x * 1 / 2x] + 2 √ [(x / y) * (Y / x)] + 2 * [y * 1 / 2Y] = 4 minimum 4

It takes 10 hours for the master to process a batch of machine parts, and 15 hours for the apprentice to process them separately. The master and the apprentice work together. When they finish the task, the master processes 30 more parts than the apprentice. How many parts are there in each batch?

Cooperation time: 1 ÷ (1 / 10 + 1 / 15) = 6 (hours)
Total number of parts: 30 (6 × 1 / 10-6 × 1 / 15) = 150 (pieces)

Solution equation: 2x-1 / 3x = 5 / 9 x + 7 / 8x = 11 / 12

2x—1/3x=5/9
5/3x=5/9
x=5/9×3/5
x=1/3
x＋7/8x=11/12
15/8x=11/12
x=11/12×8/15
x=11/45

There are two warehouses A and B. the grain stored in warehouse A is three times that of warehouse B. If warehouse A transfers 28 tons to warehouse B, warehouse a will be 4 tons more than warehouse B. how many tons of grain is there in warehouse B now

If warehouse B stores x tons of grain, warehouse A stores 3x tons of grain
According to the known equation:
（3x-28）-（x+28）=4
The solution is as follows
2x=60
x=30
3x=90
Therefore, a warehouse grain 90 tons; B warehouse grain 30 tons
Therefore, the current B warehouse has 30 + 28 = 58 tons of grain
A: now B warehouse stores 58 tons of grain

How to connect the equation 1 / 4x-4 + 1 / 3x + 14 + 90 = x?

1/4X—4＋1/3X+14+90=X
x-1/4x-1/3x=100
x-3/12x-4/12x=100
5/12x=100
x=100x12/5
x=240

The total weight of two tons of cement is 5.7 tons. Three fourths of the first pile is used and three fifths of the second pile is used. Adding up the remaining two piles, it is one fifth less than the first pile. How much cement is there in the first pile?

The first pile uses 3 / 4, the second pile uses 3 / 5, the first pile remains 1-3 / 4 = 1 / 4, the second pile remains 1-3 / 5 = 2 / 5, adding the remaining two piles together, it is 1 / 5 less than the first pile, which means that the remaining two piles are only equivalent to 1-1 / 5 = 4 / 5 of the first pile, and 2 / 5 of the second pile is equal to 4 / 5-1 / 4 = 11 / 20 of the first pile

If Sn = 3 ^ n + A, then a2s2 is equal to?

an=Sn-S(n-1)=3^n-3^(n-1)=2*3^(n-1)
a1=S1=3+a=2
a=-1
an=2*3^(n-1)
a2=6
Sn=3^n-1
S2=8

For a highway with a length of 5cm measured on the drawing with a scale of 1:30000, it takes 6 days for Party A and Party B to jointly repair it. The work efficiency ratio of Party A and Party B is 2:3. If they jointly repair it for 5 days, how many meters more will team B repair than team a?

5 △ 1 / 3 0000 = 150000 (CM) = 1500m
1500 △ 6 × 2 / 5 = 100 (m)
1500 △ 6 × 3 / 5 = 150 (m)
(150-100) × 5 = 250 (m)
If they work together for five days, team B will build 250 meters more than team a
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