Tính :
\(A=\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)...\left(1-\frac{1}{2015}\right)\left(1-\frac{1}{2016}\right)\)
giúp mk nha các bn mk đang cần gấp
Những câu hỏi liên quan
A left(frac{1}{2^2}-1right).left(frac{1}{3^2}-1right).left(frac{1}{4^2}-1right).....................left(frac{1}{2015^2}-1right).left(frac{1}{2016^2}-1right)
B frac{-1}{2}
so sánh A và B
Giúp mk nha mk đang cần gấp lắm ! Cảm ơn trước!!!!!!!!!!!
Đọc tiếp
A =\(\left(\frac{1}{2^2}-1\right)\).\(\left(\frac{1}{3^2}-1\right)\).\(\left(\frac{1}{4^2}-1\right)\).....................\(\left(\frac{1}{2015^2}-1\right)\).\(\left(\frac{1}{2016^2}-1\right)\)
B =\(\frac{-1}{2}\)
so sánh A và B
Giúp mk nha mk đang cần gấp lắm ! Cảm ơn trước!!!!!!!!!!!
Tìm x,y biết:
\(\left|x+\frac{11}{7}\right|+\left|x+\frac{2}{7}\right|+\left|x+\frac{4}{7}\right|=4x\)
\(\left(x-2\right)^{2014}+\left(y-1\right)^{2016}+\left(x-y-2\right)=0\)
mk đang cần gấp giúp mk nha các bn
Tìm x biết:a) left(x+frac{1}{2}right).left(x-frac{3}{4}right)0b) left(frac{1}{2}.x-3right).left(frac{2}{3}x+frac{1}{2}right)0c) frac{2}{3}-frac{1}{3}.left(x-frac{3}{2}right)-frac{1}{2}left(2x+1right)5d) 4x-left(x+frac{1}{2}right)2x-left(frac{1}{2}-5right)MONG CÁC BN GIÚP ĐỠ MK BÀI NÀY , MK ĐANG CẦN RẤT GẤP GIẢI CHI TIẾT RA GIÚP MK VS NHÉ !!!MK RẤT CẢM ƠN!
Đọc tiếp
Tìm x biết:
a) \(\left(x+\frac{1}{2}\right).\left(x-\frac{3}{4}\right)=0\)
b) \(\left(\frac{1}{2}.x-3\right).\left(\frac{2}{3}x+\frac{1}{2}\right)=0\)
c) \(\frac{2}{3}-\frac{1}{3}.\left(x-\frac{3}{2}\right)-\frac{1}{2}\left(2x+1\right)=5\)
d) \(4x-\left(x+\frac{1}{2}\right)=2x-\left(\frac{1}{2}-5\right)\)
MONG CÁC BN GIÚP ĐỠ MK BÀI NÀY , MK ĐANG CẦN RẤT GẤP GIẢI CHI TIẾT RA GIÚP MK VS NHÉ !!!MK RẤT CẢM ƠN!
chứng tỏ rằng:
\(\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)....\left(1-\frac{1}{2015}\right)<1\)
giúp mk nha các bn , thanks !!!!
(1 - \(\frac{1}{2}\) ) ( 1 - \(\frac{1}{3}\) )...( 1 - \(\frac{1}{2015}\) )
= \(\frac{1}{2}\) . \(\frac{2}{3}\).....\(\frac{2014}{2015}\)
= \(\frac{1.2.....2014}{2.3.....2015}\) = \(\frac{1}{2015}\) <1
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Cho E=\(\left(\frac{1}{2}+1\right)\)\(\left(\frac{1}{3}+1\right)\)\(\left(\frac{1}{4}+1\right)\)\(...\)\(\left(\frac{1}{99}+1\right)\)
Tính E ( Giúp mk nha mk đang cần gấp)
\(E=\frac{3}{2}.\frac{4}{3}.\frac{5}{4}.....\frac{100}{99}\)
\(E=\frac{3.4.5...100}{2.3.4...99}\)
\(E=\frac{100}{2}\)
\(E=50\)
k cho mk nha
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Ta có : \(E=\left(\frac{1}{2}+1\right)\left(\frac{1}{3}+1\right)\left(\frac{1}{4}+1\right)...\left(\frac{1}{99}+1\right)\)
\(\Rightarrow\) \(E=\frac{3}{2}.\frac{4}{3}.\frac{5}{4}...\frac{100}{99}\)
\(\Rightarrow\) \(E=\frac{3.4.5...100}{2.3.4...99}\)
\(\Rightarrow\) \(E=\frac{100}{2}\)
\(\Rightarrow\) \(E=50\)
Vậy E = 50
Kb vs nk mk nha m.n ^^
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Xem thêm câu trả lời
Thực hiện phép tính
a. \(25^{10}-\left(\frac{1}{5}\right)^{20}+\left(\frac{-3}{4}\right)^8-2011^0\)
b. \(\left(\frac{1}{2}-\frac{2}{3}\right)-\left(\frac{5}{3}-\frac{3}{2}\right)-\left(\frac{7}{3}-\frac{5}{2}\right)\)
Các bạn giúp mk với, mk đang cần gấp
giúp tớ giải bài này nha càng nhanh càng tốt !
Tính:S=\(\left(1-\frac{1}{^{2^2}}\right).\left(1-\frac{1}{3^2}\right).\left(1-\frac{1}{4^2}\right).....\left(1-\frac{1}{2016^2}\right)\)
Mình cần gấp các bn ạ !
\(=\frac{2^2-1}{2^2}\cdot\frac{3^2-1}{3^2}\cdot\cdot\cdot\frac{2016^2-1}{2016^2}=\frac{1.3}{2.3}\cdot\frac{2.4}{3.3}\cdot\cdot\cdot\cdot\frac{2015.2017}{2016.2016}\)
\(=\frac{\left(1.2.3....2015\right).\left(3.4....2016.2017\right)}{\left(2.3....2016\right)\left(2.3......2015.2016\right)}=\frac{2017}{2.2016}=\frac{2017}{4032}\)
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Tính nhanh :
\(A=\left(1-\frac{1}{2}\right).\left(1-\frac{1}{3}\right).\left(1-\frac{1}{4}\right).....\left(1-\frac{1}{102}\right)\)
\(B=\frac{\frac{1}{2}+\frac{1}{3}+....+\frac{1}{2016}}{\frac{2015}{1}+\frac{2014}{2}+...+\frac{1}{2015}}\)
Giúp mik nha
\(A=\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)\left(1-\frac{1}{4}\right).....\left(1-\frac{1}{102}\right)\)
\(A=\frac{1}{2}.\frac{2}{3}.\frac{3}{4}.....\frac{101}{102}=\frac{1}{102}\)
\(B=\frac{\frac{1}{2}+\frac{1}{3}+....+\frac{1}{2016}}{\frac{2015}{1}+\frac{2014}{2}+...+\frac{1}{2015}}=\frac{C}{D}\)
Ta có: \(D=\frac{2015}{1}+\frac{2014}{2}+...+\frac{1}{2015}\)(có 2015 số hạng)
\(D=\left(\frac{2015}{1}+1\right)+\left(\frac{2014}{2}+1\right)+...+\left(\frac{1}{2015}+1\right)-2015\)
\(D=2016+\frac{2016}{2}+\frac{2016}{3}+...+\frac{2016}{2015}-2015\)
\(D=\frac{2016}{2}+\frac{2016}{3}+...+\frac{2016}{2015}+1=\frac{2016}{2}+\frac{2016}{3}+...+\frac{2016}{2015}+\frac{2016}{2016}\)
\(D=2016\left(\frac{1}{2}+\frac{1}{3}+...+\frac{1}{2015}+\frac{1}{2016}\right)=2016C\)
Vậy \(B=\frac{C}{D}=\frac{C}{2016C}=\frac{1}{2016}\)
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\(A=\left(1-\frac{1}{2}\right)\cdot\left(1-\frac{1}{3}\right)\cdot\left(1-\frac{1}{4}\right)\cdot....\cdot\left(1-\frac{1}{102}\right)\)
\(A=\frac{1}{2}\cdot\frac{2}{3}\cdot\frac{3}{4}\cdot...\cdot\frac{101}{102}=\frac{1\cdot2\cdot3\cdot....\cdot101}{2\cdot3\cdot4\cdot....\cdot102}\)
\(A=\frac{1}{102}\)
\(B=\frac{\frac{1}{2}+\frac{1}{3}+...+\frac{1}{2016}}{\frac{2015}{1}+\frac{2014}{2}+...+\frac{1}{2015}}\)
\(B=\frac{\frac{1}{2}+\frac{1}{3}+...+\frac{1}{2016}}{\left(\frac{2015}{1}+1\right)+\left(\frac{2014}{2}+1\right)+...+\left(\frac{1}{2015}+1\right)+1}\)
\(B=\frac{\frac{1}{2}+\frac{1}{3}+...+\frac{1}{2016}}{\frac{2016}{1}+\frac{2016}{2}+...+\frac{2016}{2015}+\frac{2016}{2016}}\)
\(B=\frac{\frac{1}{2}+\frac{1}{3}+...+\frac{1}{2016}}{2016\cdot\left(\frac{1}{2}+\frac{1}{3}+...+\frac{1}{2016}\right)}=\frac{1}{2016}\)
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Tính tích
\(A=\left(1-\frac{1}{2010}\right)\left(1-\frac{2}{2010}\right)\left(1-\frac{3}{2010}\right)...\left(1-\frac{2011}{2010}\right)\)
GIÚP MK VỚI MK ĐANG CẦN GẤP
\(A=\left(1-\frac{1}{2010}\right)\left(1-\frac{2}{2010}\right)...\left(1-\frac{2010}{2010}\right)\left(1-\frac{2011}{2010}\right)\)
\(=\left(1-\frac{1}{2010}\right)\left(1-\frac{2}{2010}\right)...0\left(1-\frac{2011}{2010}\right)\)
\(=0\)
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