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Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
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mình cũng đang làm câu đó nghĩ ra rồi nhưng ko biết có đúng ko
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B= (1-1/2)* (1-1/3)*...............(1-1/2004)
= 1/2*2/3*........* 2003/2004
=(1*2*3*...*2003)/(2*3*4*...*2004)
= 1/2004
k cho mình nha
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a) chắc bạn cũng biết
b) \(\frac{2005.2007-1}{2004+2005.2006}=\frac{2005.\left(2006+1\right)-1}{2004+2005.2006}=\frac{2005.2006+2005.1-1}{2004+2005.2006}=\frac{2005.2006+2004}{2004+2005.2006}=1\)
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1) \(A=20,11\times2,4+1,4\times20,11\times2-10,05\times10,4\) (tách 40,22 = 20,11 x 2)
\(=20,11\times\left(2,4+1,4\times2\right)-10,05\times10,4\)
\(=20,11\times5,2-10,05\times5,2\times2\) (tách 10,4 = 5,2 x 2)
\(=5,2\times\left(20,11-20,1\right)\)
\(=5,2\times0,01\)
\(=0,052\)
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Ta có : \(\left(1+\frac{1}{100}\right).\left(1+\frac{1}{99}\right).......\left(1+\frac{1}{3}\right)\left(1+\frac{1}{2}\right)\)
\(=\frac{101}{100}.\frac{100}{99}.\frac{99}{98}......\frac{4}{3}.\frac{3}{2}=\frac{101}{2}\)
\(\left(1+\frac{1}{100}\right).\left(1+\frac{1}{99}\right).....\left(1+\frac{1}{3}\right).\left(1+\frac{1}{2}\right)\)
\(=\frac{101}{100}.\frac{100}{99}.....\frac{4}{3}.\frac{3}{2}=\frac{101}{2}\)