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 :
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Câu 8: Viết biểu thức sau thành tích 2 thừa số:
Đề bài: ab + ab x 2 + ab x 4 + ab =
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-------- Còn nữa -------
a: x*ab=abab
=>x=101
b: x*abc=abcabc
=>x=abcabc/abc=1001
Ta có: \(abab=ab\times100+ab=ab\times\left(100+1\right)=ab\times101\)
\(\Rightarrow ab\times x=ab\times101\)
\(x=101\)
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Ta có: \(abcabc=abc\times1000+abc=abc\times\left(100+1\right)=abc\times1001\)
\(\Rightarrow abc\times x=abc\times1001\)
\(x=1001\)