Phần típ theo nè!
Câu 5: Tìm \(x\):
Đề bài : \(xxx\) - \(x
\) x 105 = 30
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Câu 6: Tìm \(x \):
a) \(x \) x 7 + \(x\) = 384.
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b) \( x\)\(x
\) - \(x\) x 2 = 378.
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Câu 7: Tìm số tự nhiên ab biết ab x 9 = 2ab :
........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
Câu 8: Viết biểu thức sau thành tích 2 thừa số:
Đề bài: ab + ab x 2 + ab x 4 + ab =
........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
-------- Còn nữa -------
Giải :
a) X x ab = ab0ab
=> X = ab0ab : ab
=> X = ( ab000 + ab ) : ab
=> X = ab000 : ab + ab : ab
=> X = 1000 + 1 = 1001
Vậy X = 1001
b) abcabc : X = abc
=> X = abcabc : abc
=> X = ( abc000 + abc ) : abc
=> X = abc000 : abc + abc : abc
=> X = 1000 + 1 = 1001
Vậy X = 1001
Đáp án :
a) X = 1001
b) X = abcabc : abc
X = 101