Calculation: (1 / 3a-0.2b) (- 0.2b-1 / 3a)

Calculation: (1 / 3a-0.2b) (- 0.2b-1 / 3a)

If we know that the imaginary number (X-2) + Yi is the root 3, we can find the maximum value of Y / X
Same topic

Let (X-2) ^ 2 + y ^ 2 = 3 be a circle with (2,0) as the center and root 3 as the radius in the real coordinate system. Y / x = (y-0) / (x-0), that is, the slope of the line crossing the origin and the circle. Obviously, the first quadrant is the most tangent to the circle, and the maximum inclination angle is arcsin (root 3 / 2) = 60, (Y / x) max = tan60 = root 3

The fruit shop shipped 300 kg of apples, one fifth more than bananas. The pears transported are 80% of apples. How many kg of pears and bananas are transported?

Pear 300 × 80% = 240 (kg)
Banana 300 (1 + 1 / 5) = 250 (kg)
Pears and bananas are 240 kg and 250 kg respectively

（1/50－1）（1/49-1）（1/48-1）...（1/4-1）（1/3-1）（1/2-1）
Calculate its product

(1/50-1)(1/49-1)(1/48-1)…… (1/4-1)(1/3-1)(1/2-1)
=(-49/50)×(-48/49)×(-47/48)×…… ×(-3/4)×(-2/3)×(-1/2)
=-1/50
A total of 49 negative fractions are multiplied and the product is negative; after approximately dividing, the denominator 50 of the first fraction and the numerator 1 of the last fraction are left

Kirchhoff's law is based on the theory of steady current. From Kirchhoff's law, we can deduce that the current in series circuit is equal everywhere. What about alternating current?
How to deduce that the current in series AC circuit is equal everywhere?
In a stable circuit, the current of a series circuit is equal everywhere. What about an AC circuit?

At each time, AC circuit can be regarded as DC circuit, and the current in series circuit is equal everywhere. At different times, due to the change of power supply, the current in the circuit changes, but it is still equal everywhere

A middle school plans to organize seventh grade teachers and students to visit Dafeng Milu reserve. The following is a dialogue between grade leader Mr. Li, Mr. Wang and Mr. Chen about car rental: Mr. Li: "Ping'an passenger transport company has two types of buses with 45 seats and 35 seats to rent. The rent of each 45 seat bus is 100 yuan higher than that of 35 seats." Mr. Wang: "our eighth grade teachers and students were here yesterday Five passenger transport companies rent five 45 seat buses and three 35 seat buses to visit the milu nature reserve, with a total rent of 6100 yuan per day According to the above dialogue, answer the following questions: (1) what are the daily rental rates of 45 seat and 35 seat buses of Ping An passenger transport company? (2) Would you please design a car rental scheme for ninth grade teachers and students to rent a car in the company for one day to minimize the rent?

(1) Suppose that the daily rental of 45 seat and 35 seat passenger cars of Ping An passenger transport company is X Yuan and Y yuan respectively. From the meaning of the question, we can get: X − y = 1005x + 3Y = 6100, and the solution is: x = 800Y = 700. Answer: the daily rental of 45 seat and 35 seat passenger cars of Ping An passenger transport company is 800 yuan and 700 yuan respectively; (2) the average per capita ticket price of 45 seat passenger cars is 800 ／ 45 = 1779 yuan, and the average per capita ticket price of 35 seat passenger cars is 1779 yuan The total number of teachers and students in Grade 9: 45 × 8-20 = 340 (people), ∫ 1779 ＜ 20, renting more than 45 seats 25, rent 6 45 seat passenger cars and 2 35 seat passenger cars. At this time, there is no vacancy and the rent is the least

How to do 1-2 + 3-4 + 5-6 +. + 99-100
Do business tonight, the sooner the better

AI. 1-2 + 3-4 + 5-6 + 7-8 + 9-10 = - 5
And 1-2 +. + 99-100 has 10 such - 5, that is, it is equal to - 5 * 10 = - 50

What are the advantages of the vector synthesis method compared with the traditional method?

Compared with chemical extraction, supercritical fluid extraction (SFE) has the following advantages: (1) SFE can be used near room temperature (35 ℃), but SFE does not replace the traditional separation method as some people expect, especially 90 ℃

A train departing from a station is accelerating in a straight line at a constant speed on a straight track. It is known that the length of the train is L. when the locomotive passes a road sign, the speed is V1, and when the tail of the train passes the road sign, the speed is v2. Find out the magnitude of the train acceleration a, the speed V at the middle point of the train passing the road sign, and the time t for the whole train to pass the road sign,

1)v²－v0²=2ax v2²－v1²=2al a=v2²－v1²／2l
2) V X / 2 = V0 & sup2; + V & sup2; / 2 = V1 & sup2; + V2 & sup2; / 2
3)v=v0+at t=v-v0/a=2l/v1+v2

Lim X-2 (x3-8) / (x2-4)

(x³－8)/(x²－4)
=[(x－2)(x²＋2x＋4)]/[(x－2)(x＋2)]
=(x²＋2x＋4)/(x＋2)
The limit is: 3