My father said, "I'm sorry, I'll judge for myself." RT

My father said, "I'm sorry, I'll judge for myself." RT

Father said, I'm sorry, he will judge for himself

The young man asked me, "why don't you come here to read a book?"

The young man asked me why I didn't go to his place to read

My father firmly said to his mother, "I will not leave Beijing easily."

Father firmly told his mother that he would not leave Beijing easily

A school organized 340 teachers and students to carry out long-distance inspection activities, with 170 Pieces of luggage. It plans to rent 10 cars of two models a and B. It is understood that each car of a can carry up to 40 people and 16 pieces of luggage, and each car of B can carry up to 30 people and 20 pieces of luggage. (1) please help the school to design all feasible car rental schemes; (2) if the rent of car a is 2000 yuan per car, the rent of car B will be reduced It's 1800 yuan per car. What's the best way to save car rental?

(1) According to the meaning of the title, we can get 40x + 30 (10 − x) ≥ 34016x + 20 (10 − x) ≥ 170, and the solution is 4 ≤ x ≤ 7.5. Also, X is an integer, ∧ x = 4 or 5 or 6 or 7. There are four schemes: ① a 4, B 6; ② a 5, b 5; ③ a 6, B 4; ④ a 7

The radius of a circle is 2 cm. If the radius is increased by 1 / 2, what is its area? What is its area?
Want the simplest score

Original area: 3.14 × 2 × 2 = 12.56 square centimeter
Current area: 2 × (1 + 1 / 2) = 3cm
3.14 × 3 × 3 = 28.26 square centimeter
It's 28.26 / 12.56 = 9 / 4
Or: 3 × 3 / 2 × 2 = 9 / 4

Given the function f (x) = a Λ X-1 (1), if f (LGA) = 100, find the value of A. (2) compare the size of F (LG1 / 100) and f (- 2,1)
1) If f (LGA) = 100, find the value of A
(2) Compare the size of F (LG1 / 100) and f (- 2,1)

1、
f(lga)
=a^(lga-1)=100
Logarithm
(lga-1)lga=lg100=2
lg²a-lga-2=0
(lga-2)(lga+1)=0
lga=2,lga=-1
a=100,a=1/10
2、
lg1/100=lg10^(-2)=-2>-2.1
0

How to solve the equation (x + 15 + 15): (X-15) = 10:7,

(x+15+15):(x-15)=10:7
7(x+30)=10(x-15)
7x+210=10x-150
3x=360
x=120

If cos130 ° is a, then tan50 ° is equal to a

cos130°=cos(180°-50°)=-cos50°
Sin50 ° = under positive and negative root sign (1-A ^ 2)
Tan50 ° = sin50 ° / cos50 ° = under positive and negative root sign (1-A ^ 2) / A

Calculating average acceleration and instantaneous acceleration with derivative formula
For example, the topic gives a relationship between speed and time, which requires the average acceleration in the first three seconds and the instantaneous acceleration in the third second. How can we find it by using the derived formula, such as [(x) '= 1] [(SiNx)' = cosx]?

The velocity is the derivative of the displacement. The displacement can be obtained by integration, and the average velocity can be obtained by dividing the displacement by 3. The acceleration is the derivative of the velocity. The derivative of V can be obtained, and then the instantaneous acceleration can be obtained by making t equal to 3

The chickens and rabbits fed by Grandma's family have 20 heads and 52 feet. How many chickens and rabbits did grandma's family feed?

Set X chickens and 20-x rabbits
2X+4(20-X)=52
X=14
If the number of chickens is 14, the number of rabbits is 20-14 = 6