`***`Lời giải`***`
1)
`x^2-12x+36`
`=x^2-2.6x+6^2`
`=(x-6)^2`
Áp dụng: `(A-B)^2=A^2-2AB+B^2`
2)
`x^2+4x+4`
`=x^2+2.2x+2^2`
`=(x+2)^2`
Áp dụng: `(A+B)^2=A^2+AB+B^2`
3)
`x^2-6xy+9y^2`
`=x^2-2.3xy+(3y)^2`
`=(x-3y)^2`
`1)`
`x^2 - 12x + 36`
`= x^2 - 2x * 6 + 6^2`
`= (x-6)^2`
`2)`
`x^2 + 4x + 4`
`= x^2 + 2x*2+2^2`
`= (x+2)^2`
`3)`
`= x^2 - 2x*3y + (3y)^2`
`= (x-3y)^2`
Các hằng đẳng thức :
`(a+b)^2 = a^2+2ab+b^2`
`(a-b)^2 = a^2-2ab+b^2`
I. Put the verb in bracket into the present continuous tense or simple present tense. 1. What ____________ she (cook)________________ for dinner tonight? 2. What__________ she often (do) ___________ in the evening? 3. The last train (leave) __________ the station at 11 o’clock. 4. Keep silent! You (talk) ___________so loudly. 5. I (not stay) __________________ at home at the moment. 6. Now she (lie) __________________to her mother about her bad marks. 7. At present they (travel) ___________to New York. 8. He (not work) _____________in his office now. 9. Hoa (have)________________ a birthday party tonight. 10. We (practice) ______________ speaking English now. 11.He (paint) ____________the pictures at the moment. 12.Be careful! The car (go) _____________so fast. 13.Listen! Someone (cry) _____________in the next room. 14.Your brother (sit) ______________next to the beautiful girl over there at present? 15.Now they (try) _________________ to pass the examination. 16.It’s 12 o’clock, and my parents (cook) ____________ lunch in the kitchen. 17.She can’t stay (long) ____________giúp với
(5 căn 1/5+1/2 căn 20-5/4 căn( 4/5 +căn 5)):2 căn 5 giúp mk vs :(
Mn giải chi tiết cho e tại sao hs y=sinx lại nghịch biến trên khoảng (π/2 + k2π ; 3π/2 + k2π) ạ:(
Complete the conversations using the pairs of verbs in the box. Use “be + past participle”, “get + (object) + past participle”, or “have + (object) + past participle”. Add the object in brackets where this is supplied and give alternatives where possible. own – break into /cut – clean / catch – infect / wake up – throw out 1. A: You’re looking tired. B: I ………………………… early by my neighbor’s dog. A: Don’t they keep it inside at night? B: Usually, yes, but I think it must………… because it was barking so much. 2. A: James looked different somehow. B: He’d……………………… (his hair) A: Yes, and I think he’d……………………… It looked much smarter! (his jacket) 3. A: What an amazing house! B: It ………………… by Jason Norman. You know, the rock singer. A: I know him, yes. B: The problem is, he’s never there, and it keeps ………………………… 4. A: What happened to your coat? B: I ……… on some barbed wire as I was climbing over a fence. I hurt my arm, too. (it) A: Ouch. That looks nasty. You ought to go to the doctor. It might…………
giải thích chi tiết có ngay hay nhất nhé có hai câu nên nhanh nhé
Write a paragraph to tell about your recent journey (no more than 150 words) -có thêm nghĩa tiếng việt
Làm giúp mik bài nhảy với xá nộp r:((
cho tam giác ABC có góc BAC=a(0<a<180 độ), hai đường phân giác của góc B,C cắt nhau tại T. Tìm a biết góc BTC=2.góc BAC
Bài2: Tính bằng cách thuận tiện nhất: (2021+2019+217+...+11+9+7)×(7×8-4×12).
Giúp mình bài này với mn ơiii❤❤
Loga.vn - Cộng Đồng Luyện Thi Trực Tuyến