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An applied problem related to quadratic equation of one variable The company has 120 taxis, and the daily rent of each taxi is 160 yuan. The taxi business is in short supply every day. In order to meet the market demand, with the approval of relevant departments, the company plans to increase the daily rent appropriately. According to the market survey, for every 10 yuan increase in the daily rent of a car, the number of taxis per day will correspondingly decrease by 6. If other factors are not taken into account, the number of taxis per day will increase by 10 yuan, When the company increases the daily rent of each car, the total daily rent income of the company will be 180 yuan more than before, and a certain number of vehicles will be maintained?
Suppose the increase is 10 x yuan
10x*(120-6x)-6x*160=180
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Do it yourself
An applied problem of quadratic equation of one variable
In February, the turnover of the store was 500000 yuan, which dropped by 30% in March, rebounded in April, and increased by 5% in May to 483000 yuan compared with April?
March = 50 * (1-0.3) = 350000 yuan
Set the growth rate in April as X
There are 35 * (1 + x) = in April
In April * (1 + X + 0.05) = 48.3
So 35 * (1 + x) * (1 + X + 0.05) = 48.3
The result of solving quadratic equation of one variable
X=0.15
15%
So 15% in April and 20% in May
Add an integral to the polynomial A & # 178; + 1 to make it a complete square, and write three integers satisfying the conditions______ ,______ ,_______
2a；-1；-a²
It is known that the function f (x) = x & # 178 / / ax + B (a, B are constants), and the solution set of the inequality f (x) ≥ mx-12 (M is constant) is [x| x < 2 or 3 ≤ x ≤ 4]
(1) Finding the analytic expression of function f (x)
(2) Let k > 1, the solution of the inequality f (x) ≤ {(K + 1) x-k} / 2-x about X
(1) According to the set of inequality solutions, we can get three equations: 2A + B = 09 / (3a + b) = 3m-1216 / (4a + b) = 4m-12, we can get a = - 1, B = 2, M = 1; so f (x) = x & # 178; / (2-x) (x is not equal to 2) (2) f (x) ≤ {(K + 1) x-k} / 2-x; when X2, when k > 2, x > K
VB programming to calculate the sum of multiples of 3 in 1 ~ 100
dim x as integer,dim sum as integer
for x=1 to 100
if x mod 3 =0 then
sum=sum+x
end if
next x
print sum
How many 220v60w lamps can a meter marked with 220v5a be installed at most?
The maximum allowable electric power of electric energy meter is p = UI = 220 V * 5A = 1100 W
The power of the lamp is 60W 1100W / 60W ≈ 18.33
So you can only access 18 at most
The geometric meaning of Cauchy's mean value theorem
Cauchy mean value theorem
Let f (x) and G (x) satisfy:
(1) In the closed interval [a, b]:
(2) In the open interval (a, b), the
(3) In the interval (a, b), G '(ε) ≠ 0
Then, in (a, b), there is at least one point e such that
[f(b) - f(a)]/[g(b) - g(a)]=f'(ε)/g'(ε)
What is the geometric meaning of Cauchy mean value theorem?
If u = f (x), v = g (x), this form can be understood as a parametric equation, and [f (a) - f (b)] / [g (a) - G (b)] is the end slope of the connecting parametric curve. F '(ξ) / g' (ξ) represents the tangent slope at a point on the curve. Under the condition of the theorem, it can be understood as follows:
There is at least one point on a curve expressed by a parametric equation whose tangent is parallel to the chord of the two ends
I don't understand the details of online search
Xiao Hong has an electric water heater at home with a rated voltage of 220 v. he turns off all other electrical appliances in his home. After 10 minutes, his ammeter increases by 0.2
Calculation of rated power of electric water heater
Normal working resistance
1. If 0.2 kilowatt hour of continuous operation is achieved in 10 minutes, then 1 hour of continuous operation = 6 × 0.2 = 1.2 kilowatt hour
The rated power of this electric water heater is 1.2kW
2. According to the electric power equal to the square of the voltage divided by the resistance P = UU / R
It is concluded that the normal working resistance R = 220 × 220 △ 1200 ≈ 40 ohm
The normal working resistance of the electric water heater is about 40 ohm
Finding X / y with 5x ^ 2 + 7xy + 6y ^ 2 = 0
5x & sup2; + 7xy + 6y & sup2; = 0 (divide both sides by Y & sup2;)
5(x/y)²+7x/y+6=0
△=7²-4*5*6=49-120
When a 220 V, 60 W bulb is connected to a 220 V power supply, what is the current passing through the bulb? What is the resistance of the bulb?
Current I = P / u = 60 / 220 = 0.2727 a resistance R = u / I = 220 / 0.2727 = 806.7 ohm
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- 1. Application of quadratic equation of one variable In January 2010, the sales volume of Renming shopping mall was 1 million yuan, and the sales volume decreased by 10% in February. In March, the shopping mall took measures to reform the traffic strategy, so that the monthly sales volume increased significantly, and the sales volume in April reached 1.296 million yuan
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