giải c) d) cho mình vs
Những câu hỏi liên quan
Cho a/b =c/d .Chứng minh rằng :
a) a^2-b^2/c^2-d^2 = ab/cd
b) (a-b)^2/(c-d)^2 = ab/cd
Giải chi tiết giúp mình vs
Mình sắp nộp bài rồi ....v
mình tick cho
a, \(\frac{a}{b}=\frac{c}{d}\Rightarrow\frac{a}{c}=\frac{b}{d}\Rightarrow\frac{a^2}{c^2}=\frac{b^2}{d^2}=\frac{a^2-b^2}{c^2-d^2}\left(1\right)\)
\(\frac{a^2}{c^2}=\frac{a}{c}\cdot\frac{b}{d}=\frac{ab}{cd}\left(2\right)\)
Từ (1) và (2) => đpcm
b, Đặt \(\frac{a}{b}=\frac{c}{d}=k\Rightarrow a=bk,c=dk\)
Có: \(\left(\frac{a-b}{c-d}\right)^2=\left(\frac{bk-b}{dk-d}\right)^2=\left[\frac{b\left(k-1\right)}{d\left(k-1\right)}\right]^2=\left(\frac{b}{d}\right)^2\left(1\right)\)
\(\frac{ab}{cd}=\frac{bk.b}{dk.d}=\frac{b^2}{d^2}=\left(\frac{b}{d}\right)^2\left(2\right)\)
Từ (1) và (2) => đpcm
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a. domestic b. investment c. substantial d. undergo
làm và giải thích hộ mình vs ạ
D
Đáp án A, C từ kết thúc đuôi –ic, -ial trọng âm rơi vào trước nó
Đáp án B đuôi –ment không nhận trọng âm xét nguyên thể invest trọng âm thứ 2
Đáp án D /ˌʌn.dəˈɡəʊ/
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Trong cùng một hệ trục tọa độ Oxy cho p: y=(1/2)x^2 và đường thẳng d: y= mx -2m-1 b tìm m sao cho d tiếp xúc vs p Giải chi tiết giúp mình vs nhé
PTHĐGĐ là:
1/2x^2-mx+2m+1=0
Δ=(-m)^2-4*1/2(2m+1)
=m^2-4m-2
Để (P) tiêp xúc (d) thì m^2-4m-2=0
=>\(m=2\pm\sqrt{6}\)
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Phương trình hoành độ giao điểm của (P) và (d):
1/2 x² = mx - 2m - 1
⇔ x² = 2mx - 4m - 2
⇔ x² - 2mx + 4m + 2 = 0
Để (P) và (d) tiếp xúc thì phương trình hoành độ giao điểm của chúng có nghiệm kép
⇔ ∆´ = 0
⇔ m² - 4m - 2 = 0
∆´ = 4 + 2 = 6
m₁ = 2 + √6
m₂ = 2 - √6
Vậy m = 2 + √6; m = 2 - √6 thì (P) và (d) tiếp xúc
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M.n giúp mình bài này vs:( mình cần gấp nhé, m.n ghi đầy đủ lời giải hộ mình vs, mình cảm ơn trước nhé)
Cho tam giác ABC vuông tại A. Lấy D thuộc BC sao cho BA=BD. Từ D kẻ đường thẳng vuông góc BC, cắt AC tại E
a) Chứng minh: tam giác ABE= tam giác DBE
b)DE cắt BA tại F. Chứng minh: EF=EC
c) Chứng minh: BE là trung trực của AD
a) tam giac ABE=DBE (canh huyen -canh goc vuong )
(chac la biet lam nhi?)
b) vi tam giac ABE=tam giac DBE
=>AE=ED
va goc ABE =goc EBD hay goc FBE= goc CBE
xet tam giac FAE va tam giac CDE co:
AE=ED(cmt)
goc FAE=goc CDE(=90)
goc AEF =goc CED(doi dinh)
=>tam giac FAE=tam giac CDE(g.c.g)
=> EF=EC
c)ta co:BD=AB(cmt)
=>B cach deu 2 đầu mút đoạn thẳng AD
=>B thuộc đường trung trực của AD (1)
lai co:AE=ED(cmt)
=>E cach deu 2 đầu mút đoạn thẳng AD
=>E thuộc đường trung trực của AD (2)
tu (1) va (2) =>BE la duong trung truc cua AD
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15 tháng 7 2021 lúc 9:36
nhờ các bạn giải hộ mình bài này vs (mình cảm ơn)IV. Choose the best answer A, B, C, or D to complete each sentence.1.Ms. Jones isn’t as nice …….. Ms. Smith.A. as B. for C. like D. to2. The rooms in Graduate Towers are……….. Patterson Hall.A. larger than B. larger than that ofC. larger than those in D. larger than in3. Although she is very popular, she is not……her sister.A. pretty...
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nhờ các bạn giải hộ mình bài này vs (mình cảm ơn)
IV. Choose the best answer A, B, C, or D to complete each sentence.
1.Ms. Jones isn’t as nice …….. Ms. Smith.
A. as B. for C. like D. to
2. The rooms in Graduate Towers are……….. Patterson Hall.
A. larger than B. larger than that of
C. larger than those in D. larger than in
3. Although she is very popular, she is not……her sister.
A. pretty as B. as pretty
C. prettier than D. most pretty than
4. Tuition at an American university runs……. Six thousand dollars a semester.
A. so high as B. as high to
C. as high as D. as high than
5. Everyone looks much………. today than they did yesterday.
A. happy B. happily C. more happily D. happier
6. Mr. Brown receives a …….. salary than anyone else in the company.
A. big B. more bigger C. bigger D. the bigger
7. The Boeing 747 is twice…….. the Boeing 707.
A. bigger than B. as bigger as
C. as big as D. more bigger than
8. “Do you know that beautiful lady over there?” “ Yes, that’s Wanida. She’s…………. in her group.”
A. more beautiful than any girl B. more beautiful than any other girl
C. so beautiful as other girl D. beautiful more than another girl
9. My young brother grew very quickly and soon he was……..my mother.
A. more big than B. so big than
C. as big as D. too big than
10.He is not……. tall as his father.
A. the B. as C. than D. more
11. John’s grade……. than his sister’s.
A. higher B. more high C. more higher D. the highest
12. She speaks English as……….as her friend does.
A. good B. well C. better D. the best
13. He works more ………..than I.
A. slow B. slowly C. most slowly D. slowest
14. My book is as……….as yours.
A. good B. well C. better D. the best
15. I love you……….than I can say.
A. much B. many C. more D. the most
16. It’s………….to go by bus than by car.
A. cheaper B. cheapest C. more cheap D. more cheaper
17. This hotel must be………..than the small one next door.
A. expensive B. more expensive
C. the most expensive D. the more expensive
17. An orange is ……… than a plum.
A. more large B. more larger C. larger D. the largest
18. This river is……… than that river.
A. narrow B. narrowest C. narrower D. most narrow
19. The test is not………difficult……….it was last month.
A. as/ as B. so/ as C. more/ as D. A and B
20. Peter usually drives………..Mary.
A. more fast B. more fast than C. faster than D. B and C
21. The hotel was…….any one we had stayed at before.
A. more expensive than B. more expensive as
C. most expensive than D. better expensive than
22. A: It’s a long way from Britian, isn’t it?
B: Yes, but it isn’t as……….as Hong Kong.
A. far B. farther C. farthest D. further
23. The larger the apartment, the................... the rent.
A. expensive B. more expensive C. expensively D. most expensive
24. She plays the piano …………… as she sings.
A. as beautifully B. more beautifully
C. as beautiful D. the most beautifully
25. The streets are getting more and …………… these days.
A. crowded B. less crowded C. more crowded D. most crowded
26. The larger the city, …………… the crime rate.
A. highest B. higher C. the highest D. the higher
27. You must explain your problems …………....
A. as clear as you can B. as clearly as you can
C. as clear than you are D. as clearly as you are
28. Her grandfather’s illness was…………………..we thought at first.
A. more seriously as B. as seriously as C. more serious than D. as serious than
29. My brother was feeling tired last night, so he went to bed…………..usual.
A. more early than B. as early as C more earlier as D. earlier than
IV. Choose the best answer A, B, C, or D to complete each sentence.
1.Ms. Jones isn’t as nice …….. Ms. Smith.
A. as B. for C. like D. to
2. The rooms in Graduate Towers are……….. Patterson Hall.
A. larger than B. larger than that of
C. larger than those in D. larger than in
3. Although she is very popular, she is not……her sister.
A. pretty as B. as pretty
C. prettier than D. most pretty than
4. Tuition at an American university runs……. Six thousand dollars a semester.
A. so high as B. as high to
C. as high as D. as high than
5. Everyone looks much………. today than they did yesterday.
A. happy B. happily C. more happily D. happier
6. Mr. Brown receives a …….. salary than anyone else in the company.
A. big B. more bigger C. bigger D. the bigger
7. The Boeing 747 is twice…….. the Boeing 707.
A. bigger than B. as bigger as
C. as big as D. more bigger than
8. “Do you know that beautiful lady over there?” “ Yes, that’s Wanida. She’s…………. in her group.”
A. more beautiful than any girl B. more beautiful than any other girl
C. so beautiful as other girl D. beautiful more than another girl
9. My young brother grew very quickly and soon he was……..my mother.
A. more big than B. so big than
C. as big as D. too big than
10.He is not……. tall as his father.
A. the B. as C. than D. more
11. John’s grade……. than his sister’s.
A. higher B. more high C. more higher D. the highest
12. She speaks English as……….as her friend does.
A. good B. well C. better D. the best
13. He works more ………..than I.
A. slow B. slowly C. most slowly D. slowest
14. My book is as……….as yours.
A. good B. well C. better D. the best
15. I love you……….than I can say.
A. much B. many C. more D. the most
16. It’s………….to go by bus than by car.
A. cheaper B. cheapest C. more cheap D. more cheaper
17. This hotel must be………..than the small one next door.
A. expensive B. more expensive
C. the most expensive D. the more expensive
17. An orange is ……… than a plum.
A. more large B. more larger C. larger D. the largest
18. This river is……… than that river.
A. narrow B. narrowest C. narrower D. most narrow
19. The test is not………difficult……….it was last month.
A. as/ as B. so/ as C. more/ as D. A and B
20. Peter usually drives………..Mary.
A. more fast B. more fast than C. faster than D. B and C
21. The hotel was…….any one we had stayed at before.
A. more expensive than B. more expensive as
C. most expensive than D. better expensive than
22. A: It’s a long way from Britian, isn’t it?
B: Yes, but it isn’t as……….as Hong Kong.
A. far B. farther C. farthest D. further
23. The larger the apartment, the................... the rent.
A. expensive B. more expensive C. expensively D. most expensive
24. She plays the piano …………… as she sings.
A. as beautifully B. more beautifully
C. as beautiful D. the most beautifully
25. The streets are getting more and …………… these days.
A. crowded B. less crowded C. more crowded D. most crowded
26. The larger the city, …………… the crime rate.
A. highest B. higher C. the highest D. the higher
27. You must explain your problems …………....
A. as clear as you can B. as clearly as you can
C. as clear than you are D. as clearly as you are
28. Her grandfather’s illness was…………………..we thought at first.
A. more seriously as B. as seriously as C. more serious than D. as serious than
29. My brother was feeling tired last night, so he went to bed…………..usual.
A. more early than B. as early as C more earlier as D. earlier than
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IV. Choose the best answer A, B, C, or D to complete each sentence.
1.Ms. Jones isn’t as nice …….. Ms. Smith.
A. as B. for C. like D. to
2. The rooms in Graduate Towers are……….. Patterson Hall.
A. larger than B. larger than that of
C. larger than those in D. larger than in
3. Although she is very popular, she is not……her sister.
A. pretty as B. as pretty
C. prettier than D. most pretty than
4. Tuition at an American university runs……. Six thousand dollars a semester.
A. so high as B. as high to
C. as high as D. as high than
5. Everyone looks much………. today than they did yesterday.
A. happy B. happily C. more happily D. happier
6. Mr. Brown receives a …….. salary than anyone else in the company.
A. big B. more bigger C. bigger D. the bigger
7. The Boeing 747 is twice…….. the Boeing 707.
A. bigger than B. as bigger as
C. as big as D. more bigger than
8. “Do you know that beautiful lady over there?” “ Yes, that’s Wanida. She’s…………. in her group.”
A. more beautiful than any girl B. more beautiful than any other girl
C. so beautiful as other girl D. beautiful more than another girl
9. My young brother grew very quickly and soon he was……..my mother.
A. more big than B. so big than
C. as big as D. too big than
10.He is not……. tall as his father.
A. the B. as C. than D. more
11. John’s grade……. than his sister’s.
A. higher B. more high C. more higher D. the highest
12. She speaks English as……….as her friend does.
A. good B. well C. better D. the best
13. He works more ………..than I.
A. slow B. slowly C. most slowly D. slowest
14. My book is as……….as yours.
A. good B. well C. better D. the best
15. I love you……….than I can say.
A. much B. many C. more D. the most
16. It’s………….to go by bus than by car.
A. cheaper B. cheapest C. more cheap D. more cheaper
17. This hotel must be………..than the small one next door.
A. expensive B. more expensive
C. the most expensive D. the more expensive
17. An orange is ……… than a plum.
A. more large B. more larger C. larger D. the largest
18. This river is……… than that river.
A. narrow B. narrowest C. narrower D. most narrow
19. The test is not………difficult……….it was last month.
A. as/ as B. so/ as C. more/ as D. A and B
20. Peter usually drives………..Mary.
A. more fast B. more fast than C. faster than D. B and C
21. The hotel was…….any one we had stayed at before.
A. more expensive than B. more expensive as
C. most expensive than D. better expensive than
22. A: It’s a long way from Britian, isn’t it?
B: Yes, but it isn’t as……….as Hong Kong.
A. far B. farther C. farthest D. further
23. The larger the apartment, the................... the rent.
A. expensive B. more expensive C. expensively D. most expensive
24. She plays the piano …………… as she sings.
A. as beautifully B. more beautifully
C. as beautiful D. the most beautifully
25. The streets are getting more and …………… these days.
A. crowded B. less crowded C. more crowded D. most crowded
26. The larger the city, …………… the crime rate.
A. highest B. higher C. the highest D. the higher
27. You must explain your problems …………....
A. as clear as you can B. as clearly as you can
C. as clear than you are D. as clearly as you are
28. Her grandfather’s illness was…………………..we thought at first.
A. more seriously as B. as seriously as C. more serious than D. as serious than
29. My brother was feeling tired last night, so he went to bed…………..usual.
A. more early than B. as early as C more earlier as D. earlier than
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giải giúp mình vs minh cho 2 like
Cho A=a+b-5
B= -b-c+1
C=b-c-4
D=b-a
Chứng minh A+B=C-D
A+B=C-D
=> (a+b-5)+(-b-c+1)=(b-c-4)-(b-a)
=> a+b-5-b-c+1=b-c-4-b+a
=> a-c-4=a-c-4 (đpcm)
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1. A. happen B. enter C. award D. ridden
2. A. culture B. parade C. weather D. cannon
3. A. receive B. finish C. direct D. compete
4. A. visit B. famous C. wonder D. protect
5. A. critic B. event C. machine D. mistake
Ai giúp mình vs giải thích nx
1 A happen B enter C award D ridden
2 A culture B parade C weather D cannon
3 A receive B finish. C direct D compete
4 A visit B famous C wonder D protect
5 A critic B event C machine D mistake
sai thì thôi
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1 A happen B enter C award D ridden
2 A culture B parade C weather D cannon
3 A receive B finish. C direct D compete
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1C
2B
3B
4A
5A
ĐÓ LÀ Ý KIẾN RIÊNG CỦA MÌNH! SAI THÌ MONG BẠN THÔNG CẢM. CHÚC BẠN HỌC TỐT
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cho góc nhọn xOy. trên tia Ox lấy điểm A, trên tia Oy lấy điểm B sao cho OA = OB. trên tia Ax lấy điểm C, trên tia By lấy điểm D sao cho AC = BD. a) chứng minh rằng: AD = BC. b) gọi E là giao điểm AD và BC. chứng minh: ΔEAC = tam giác EBD c) chứng minh: OE là phân giác của góc xOy OE vuông góc vs CD
GIẢI GIÚP MÌNH VS Ạ . MÌNH CẦN GẤP !!!!!!
Cho tam giác ABC vuông tại A . AB/AC 4/5 , AC 18 cm a, Tính AB , BC b, Vẽ phân giác BD . Lấy H thuộc AB sao cho AH/AB 1/3 . Từ B kẻ đường thẳng vuông góc vs HC tại E . Đường thẳng BE cắt AC tại F . Tính AD , DC c, CM: Tam giác HAC đồng dạng vs tam giác HEB d, CM : Trên tia đối tia FA lấy M sao cho FM 2FA . CM : MB vuông góc vs BC • Mọi ng giúp mình với , hoặc chỉ mình cách làm cũng được hoặc giải cho mình câu a, thôi còn câu khác mình tự giải . Nghĩ mãi ko ra mà chiều mình đi học rồi , mọi ng c...
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Cho tam giác ABC vuông tại A . AB/AC =4/5 , AC= 18 cm
a, Tính AB , BC
b, Vẽ phân giác BD . Lấy H thuộc AB sao cho AH/AB =1/3 . Từ B kẻ đường thẳng vuông góc vs HC tại E . Đường thẳng BE cắt AC tại F . Tính AD , DC
c, CM: Tam giác HAC đồng dạng vs tam giác HEB
d, CM : Trên tia đối tia FA lấy M sao cho FM = 2FA . CM : MB vuông góc vs BC
• Mọi ng giúp mình với , hoặc chỉ mình cách làm cũng được hoặc giải cho mình câu a, thôi còn câu khác mình tự giải . Nghĩ mãi ko ra mà chiều mình đi học rồi , mọi ng cố gắng giúp mình nhé , mình cảm ơn trước !
Cho hình thang ABCD có góc A = góc D = 90 độ. Tia phân giác góc C đi qua trung điểm M của AD. Gọi E là hình chiếu của M trên BC. Tính số đo góc AEB. Mn giải giúp mình vs nhé.