Đáp án:
Giải thích các bước giải:
`B=\frac{1}{\sqrt{x}}`
ĐK: `x > 0`
Để giá trị BT A gấp 3 lần giá trị BT B
`A=3B`
`⇔ 1=\frac{3}{\sqrt{x}}`
`⇔ \sqrt{x}=3`
`⇔ x=9\ (TM)`
Vậy khi `x=9` thì giá trị BT A gấp 3 lần giá trị BT B
$x=9$
$A=3B$
$⇒$$1=3\dfrac{1}{\sqrt[]{x}}$ với $x>0$
$⇔$$\sqrt[]{x}=3$
$⇔x=±9$
Do $x>0⇒x=9$
Vậy $x=9$
I . Put the verbs into correct forms (1,5p). 1. He did not expect (invite)............................................ to the party. 2. (Fail) ........................................twice, he didn’t want to try again. 3. They went home after they (finish) …………………..their work. 4. (you/watch)…………………………….TV last night? 5. The teacher congratulated me on (make) ................................such a clear speech. 6. Mr Barron (study) .............................................. French since 2007. II. Rewrite the following sentences as suggested. (2,5p) 1. "What is your hobby?" Hoa asked Nam. Hoa asked.................................................................. 2. I don’t know her phone number, so I can’t call her now. If .......................................................................................... 3. I started working here 3 years ago. I have 4. "I'm terribly sorry I'm late" said Flora. → Flora apologized ......................................................................................... 5. The safeguard locked all the door. He left the office (perfect participle). → .........................................................................
Em đang cần gấp nhanh nha mọi người
Calli Mỡ, Từ giờ sẽ đặt nick name là mỡ nha! Ko bt có ai đặt trước chx nx :333
hòa tan 8,1g oxit của một kim loại hóa trị ii vào dung dịch hcl dư kết thúc phản ứng thu được 13,6g muối clorua tương ứng. xác định công thức hóa học của oxit kim loại nói trên. Làm cụ thể giúp mình với ạ. Mình cảm ơn trước nha🥰
Giúp mình với!!!!!!!!cảm ơn trước nhé
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cho tam giác abc nhọn , đường cao AE, CI cắt nhau tại H. a) CMR; tam giác AIH đồng dạng tam giác AEB b) CMR: góc ABH= góc AEI c) BH cắt AC tại D. CMR:BH.BD+CH.CI=BC bình d) DI cắt BC tại M. CMR: MI.MD=MB.MC mn giúp mình với ạ
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