Cho tam giác OBM vuông tại O, đường phân giác góc B cắt cạnh OM tại K. Trên cạnh BM lấy điểm I sao cho BO = BI

a, C/m : Tam giác OBK = Tam giác IBK

b, C/m : KI vuông góc tại BM

c, Gọi A là giao điểm của BO và IK. C/m : KA = KM

Chứng minh rằng 8⁷ - 2¹⁸ chia hết cho 14

Hãy tính giá trị biểu thức sau :

a, A = 120 : {60 : [( 3² + 4² ) - 5 ]}

b, B = 1/2 + 1/3 - 1/6

c, C = l 4 - 6 l + 2

d, D = 2² + 2³ + 3² + 3³ - 48

giúp mình vs , please :(((((

Change these sentences into passive

1, No one used this computer yesterday

2, My grandmother named my daughter after a kind of flower

3, Nobody informed me about the change of the plan

4, They gave Linh an Ox dictionary last semester

5, Tuan's parents sent him to a high quality school last year

6, Do they put garbage bin along the streets in your town !

7, The manager didn't phone the secretary this morning

Conditional Sentences

1, Mary ( Leave ) school six years ago

2, Mrs Ly ( wait ) for us one hour ago

3, We ( arrive ) this morning

4, When you last ( phone ) him ? Some week ago

5, Typhoons usually ( occur ) in autumn in our country

6, S.O ( knock ) at the door . l ( open ) it

7, Ba is a hard - working student . He always ( get ) good mark

8, Marry ( taste ) a lot of delicious food when she ( visit ) Hue

9, My brother ( leave ) university in 1998

10, The first jeans ( appear ) in Europe

11, Look at those boys , what game they ( play ) ?

12, Yesterday evening , my sister ( be ) tired , so she ( go ) to bed early

13, Farmers ( grow ) rice and ( raise ) cattle for a living

14, It's 10 o'clock now. My mother ( do ) the gardening

15, Twen diren the TV . He ( study ) for his entrance exam

Change sentences into passive

1, The studens are doing an exercise at the moment.

2, They are decorating their rooms for Tet holiday .

3, People speak English in many African countries.

4, People don't grow maize in this region.

5, Mr.Nam is reparing the faucet in the bathroom.

6, What book are you reading.

7, Do they hold a school meeting every month.

8, They don't allow us to walk on the glass

9, They are building a factory to recycle waste paper in this city

10, Nam often look after his children at the weekend ?

11, My mother often tell the folktales everynight.

12, My family spends little electricity

13, I buy some books every month

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