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 $x=9$
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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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