A is greater than 0, B is greater than 0, AB is greater than or equal to a + B + 1, find the minimum value of a + B

A is greater than 0, B is greater than 0, AB is greater than or equal to a + B + 1, find the minimum value of a + B

AB is greater than or equal to a + B + 1
That is ab ≥ a + B + 1
That is, a + B + 1 ≤ ab ≤ [(a + b) / 2] &;
That is, a + B + 1 ≤ [(a + b) / 2] &;
Let t = a + B, then t > 0
Then t + 1 ≤ [T / 2] &# 178; = 1 / 4 * t & # 178;
That is T & # 178; - 4t-4 ≥ 0
The solution is t ≥ (2 + 2 times root 2) or t ≤ (2-2 times root 2) (rounding off)
T ≥ (2 + 2 times root 2)
That is, (a + b) ≥ (2 + 2 times root 2)
The minimum value of a + B is 2 + 2 times root 2

100+99-98-97+96+95-94-93…… +8+7-6-5+4+3-2-1=?
Please write down the process, to be concise!

The original formula = (100 + 99-98-97) + (96 + 95-94-93) + +(8+7-6-5)+(4+3-2-1)
=25 times 4
=100

1 + 2 + 3 + 4 + 5 + 6 + 7. + 95 + 96 + 97 + 98 + 99 + 100

5050

Calculation formula of circumference

Perimeter = diameter x3.14

Calculation formula of half circumference

Half of the circumference of a circle can be calculated by dividing the circumference of a circle by 2. C = π r = 1 / 2 π D
The circumference formula of semicircle;
C=πr+2r=1/2πd+d

Calculation formula of circumference

L = 2 π R (R is the radius)

What's the formula for calculating the circumference of a circle?

π D, PI times diameter, or PI x radius x 2

Summary of chemistry knowledge points of PEP senior one
To have a detailed knowledge, not only chemical equations

Summary of senior one chemistry

In the first chapter, the knowledge network of "learning chemistry from experiments" is summarized. 1. Separation and purification of mixtures. 1. Basis: filtration in different states. 2. Separation of insoluble solid substances from liquid. 3. Example: removal of sediment in salt. 1. Basis: evaporation in different volatilities. 2. Separation of insoluble solid substances from solution

Knowledge and summary of chemistry in senior one

(1) reaction between elemental and oxygen: (compound reaction) 1. Combustion of magnesium in air: 2mg + O2 ignites 2MgO 2. Combustion of iron in oxygen: 3Fe + 2O2 ignites Fe3O4 3. Heating of copper in air: 2Cu + O2 heating 2CuO 4. Combustion of aluminum in air: 4Al + 3O2 point