giúp mik câu B cho phương trình 2x^2-4x-1=0 có 2 nghiệm x1 x2 .

A.Tính giá trị của biểu thức T= x1^3 - x2^3( câu này mik ra kết quả r)

B. Lập 1 phương trình bậc 2 một ẩn có 2 nghiệm là 2x1-x2^2 và 2x2-x1^2

GIÚP MIK VS 

giúp mik làm câu c với

help mik câu c vs

It was .......that it was going on rain( predict)

..............ash showed đơn to the tơn after the eruption( volcano)

giải thích giúp mình câu C sao lại chứng minh góc OFI và góc IAF vậy

1. Here is tomorrow’s weather forecast . Hanoi will ……………temperatures between 22C and 28C.
A. behave B. suffer C. welcome D. experience
2 Tidal waves are the result of an ................shift in the underwater movement of the Earth .
A. amazing B. alternative C. abrupt D. unpleasant
3. Thousands of people were saved because scientists had ...............them about the volcanic eruption.
A. said B. spoke C. warned D. talked
4. When a tropical……………. reaches 120 kilometers per hour , it’s called a typhoon in Asia .
A.rain B. wind C. cloud D. storm
5. A funnel-shaped storm pass overland below a thunderstorm is called a ..................
A. typhhon B. tidal wave C. tornado D. cyclone
6. You’d better take your coat with you ……………the weather changes.
A. although B. unless C. in case D. because
7.Tornadoes are funnel-shaped ................ which pass overland below a thunderstorm
A. storms B. winds C. rains D. snows
8. A huge earthquake ………......…a city of Kobe in Japan in 1995.
A. clapped B. bit C. struck D. kicked
9. When a tropical …………...reaches 120km/h, it is called a typhoon an Asia.
A. rain B. storm C. wind D. cloud
10. The last tsunami caused a lot of …………….to the countries along the Pacific coast.
A. eruption B. disasters C. destructio D. damage