Cho hình thang ABCD (AB//CD) có góc A = 90o; Góc B= 2 góc C.

a) Tính góc B và C

b) Gọi M và N lần lượt là trung điểm của AB và BC. Cho AB= 6cm; MN= \(\sqrt{13}\)cm. Tính CD?

Tính chu vi hình tam giác ABC (như hình vẽ).

Giải phương trình  0 x e 2 t dt = 1 2 e 2018 − 1

A. x = 2019

B.  x = 1009

C.  x = 2018

D.  x = 2017

20000 đồng 

tick nha

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct work for each of the blanks.

   During the last 400 years, most scientists have (17) ________on mathematics in their development of their inventions or discoveries. However, one great British scientist, Michael Faraday, did not make (18)__________of mathematics. Faraday, the son of a poor blacksmith, was born in London in 1791 and had no (19) _________beyond reading and writing.

   In 1812 Faraday was hired as a bottle washer by the great chemist Humphry Davy. Later, Faraday became a greater scientist than Davy, making the last years of Davy's life embittered (20) __________ jealousy. Faraday made the first (21)__________motor in 1821, a device that used electricity to produce movement.

Question 21:

A. electric

B. electrical

C. electricity

D. electrician's

Tính tích tất cả các nghiệm của phương trình  log 2 2 x + log 2 x = 17 4 .

A.  17 4

B.  1 4

C.  3 2

D.  1 2