Đáp án:
GTNN `B=17,5<=>x=3/4` và `y=-77/50`
Giải thích các bước giải:
`B=|4x-3|+|5y+7,7|+17,5`
Vì `|4x-3|>=0`
`\qquad |5y+7,7|>=0`
`=>|4x-3|+|5y+7,7|>=0`
`=>|4x-3|+|5y+7,7|+17,5>=17,5`
`=>B>=17,5`
Dấu "=" xảy ra khi `4x-3=0` và `5y+7,7=0`
`<=>4x=3` và `5y=-7,7`
`<=>x=3/4` và `y=-77/50`
Vậy GTNN `B=17,5<=>x=3/4` và `y=-77/50`
Đáp án + Giải thích các bước giải:
Vì $\begin{cases} |4x-3|\ge0\ ∀\ x \\ |5y+7,7|\ge0\ ∀\ y \end{cases}$
`=>|4x-3|+|5y+7,7|>=0\ ∀\ x;y`
`=>|4x-3|+|5y+7,7|+17,5>= 17,5\ ∀x;y`
Dấu `=` xảy ra khi :
$\begin{cases} 4x-3=0\\ 5y+7,7=0\end{cases}$
`<=>` $\begin{cases} x=\dfrac{3}{4}\\ y=-\dfrac{77}{50}\end{cases}$
Vậy `min=17,5<=>x=3/4;y=-77/50`
Cho tam giác ABC cân tại A, góc A=100 độ, trên tia đối của BA lấy điểm D sao cho AD=BC. Tính góc ADC Làm nhanh giúp mình vẽ cả hình nhé
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16. Do you agree with the famous saying “The happiest people are those who bring _______ to others?” (HAPPY) 17. We’d like to offer your school a ______ of 2 million dong. (DONATE) 18. The volunteers also help the _______ with their housework. (OLD) 19. We participate in a campaign to provide _______ for poor children. (EDUCATE) 20. I like helping _______ children to read and write. (MINOR) 21. We started a campaign for _______ eradication in the summer of 2000. (LITERATE) 22. Many ethnic minority students from the ________ Highlands took part in the campaign. (NORTH) 23. I think this is an _______ way to help people in remote and mountainous areas to read and write. (AFFECT) 24. We consider it an _______ job to help poor in our home village. ( HONOUR) 25. Are there any people unable to read and write in your _______. (NEIGHBOUR) 26. The number of literate females fell _______ between 1998 and 2004. (DRAMA) giúp em ạ, em cảm ơn
ai nhanh và đúng 5 sao, 1 câu trả lời hay
mk cần gấp. bạn nào trả lời nhanh nhất mình vote 5 sao và cho ctlhn Bài 6*: Tìm các số nguyên x, y thõa mãn: a/ x^2 – y^2 = 7; b/ x^2 = y^2 + 13; c/ x^2 = y^2 – 2y + 12; d/ x^2 – 4y^2 = 4y + 7; e/ y^2 = x^2 + x + 6;
I.The following passage contains ten errors. Find and correct them. Things started to go wrongly as soon as we got to the hotel. We were all completely exhaustingafter our long journey and looking forward to a shower and a rest. However, we found that our room was not ready, which was very annoyed, although the manager was extremely apologising. While we were waiting, we asked about the excursions to places of an interest which we have readabout in the brochure. Imagine how we felt when we were told they had all been cancelled! Apparently, the person responsible of organizing them had left suddenly and had not been replaced. Then Sally saw a notice pinning to the door of the restaurant, said it was closed for redecoration, and Peter discovered that the swimming pool was empty. When we eventually got to our room we were horrified to find that it was at the back of the hotel, and we had a view of a car park, that seemed to be used as a rubbish dump. We seriously began to wonder whether or not to stay.
Mong các bn giúp mik. MIK CẦN GẤP AK
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