Hoàng Nguyễn

Bài 1: Cho tam giác ABC vuông tại A và đường cao AH. Cmr:

Cmr: HB/HC=(AB/AC)2

Bài 2: Cmr : Với z,b ≥ 0 và c.d ≥ 0. Ta có được: √a.b+√c.d≤√(a+c).(b+d)

Bài 3: So sánh A và B, biết:

A= √123−√111 và B= √29−√17

Giúp mình với!

Rewrite the second sentences in such a way that it has the same meaning as the one before it:

1. The architect has drawn plans for an extension of the house

➜Plans............

2.They haven't cleaned the streets this week

➜The streets............

3.No one has signed this cheque

➜This cheque ....................

4.He couldn't repair the broken vase

➜The ......................

5.They'll have to change the date of the meeting agian

➜The date.................

6.The robber made the bank manager hand over the money

➜The bank manager...................

7.The postman was bitten by our dog

➜Our dog..................

8.They will catch all the prisoners again by tonight

➜All the prisoners...............

9.Sally was given a microcomputer for her birthday by her parents

➜Sally's parents.............

10.Someone has stolen my bike

➜My bike................

11.The mechanic serviced my car last week

➜I...........................

12.They don't eat the cake because it is very bad

➜The cake......................

13.The garage is going to repair the car for us next week

➜We.........................

14.Somebody repaired her car yesterday

➜She.........................

15.That old house at the end of the road has been sold

➜They.......................

16.My suit needs to be cleaned befor the interview

➜I must........................

17.Mr.Dryden mended the washing machine for me

➜I had................................

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