izuku midoriya

ko biết

a) \(1-2018sin\left(2019x+2020\right)\)

có: \(-1\le sin\left(2019x+2020\right)\le1\)

\(-2018\le2018sin\left(2019x+2020\right)\le2018\)

\(-2017\le1-2018sin\left(2019x+2020\right)\le2019\)

b) \(1+\sqrt{5+4cos3x}\)

có: \(-1\le cos3x\le1\)

\(-4\le4cos3x\le4\)

\(1\le5+4cos3x\le9\)

\(1\le\sqrt{5+4cos3x}\le3\)

\(2\le1+\sqrt{5+4cos3x}\le4\)

c) \(y=\sqrt{3}sin5x-cos5x\)

Đặt \(\sqrt{3}sin5x-cos5x=c\)

Điều kiện có nghiệm của phương trình này là \(c^2\le\left(\sqrt{3}\right)^2+1^2=4\Leftrightarrow-2\le c\le2\)

do đó \(-2\le\sqrt{3}sin5x-cos5x\le2\)

d) \(5+4sin2x.cos2x=5+2sin4x\)

\(-1\le sin4x\le1\)

\(-2\le2sin4x\le2\)

\(3\le5+2sin4x\le7\)

Số cách có thể lấy : 10C1 = 10

Số thẻ không chia hết cho  3 : 7 => Số cách chọn : 7C1 = 7

=> Xác suất : 7/10

1. He lost his money simply because he wasn't careful. (If)

=> If he hadn't been careless , he woundn't have lost his money

2. He didn't hurry, so he missed the train. (If)

=> If he had hurried, he could have caught the train.

3. We didn't go because it rained. (If it hadn't)

=> If it hadn't rained we would have gone

4. Without this treatment, the patient would have died. (If he)

=> If it hadn’t been for this treatment, the patient would have died.

5. Mr.Mills lost his job because he was late every day. ( If Mr.Mills)

=> If Mr Mills hadn't been late everyday ,he wouldn't have lost his job

6. We didn't go on holiday because we didn't have enough money. (If we)

=> . If we had had enough money we would have gone on holiday.

1. He lost his money simply because he wasn't careful. (If)

=>if he had been cafeful, he would not have lost his money

2. He didn't hurry, so he missed the train. (If)

=>If he had hurried, he would have missed.

3. We didn't go because it raines. (If it hadn't)

=>If it hadn't rained, we would have gone.

4. Without this treatment, the patient would have died. (If he)

=>If he hadn't been for this treatment, the patient would have died

5. Mr.Mills lost his job because he was late every day. ( If Mr.Mills)

=>If Mr.Mills losts his job ,he lates every day

6. We didn't go on holiday because we didn't have enough money. (If we)

=> If we had had enough money, we would have gone holiday

7. I was sick yesterday, so I didn't go to class (If)

=>If I am sick, I don't go to school

8. Because Alan never eats breakfast, he always overeats at lunch (If)

=>If Alan never eats breakfast, he always overeats at lunch

9.Fred wouldn't do that if he didn't have your permission (Unless)

=>Unless Fred had your permission, he wouldn't for that

10. If no more guests come, there will be enough food for everyone. (Unless)

=>Unless no more guests come, there will not be enough food for everyone