Ôn tập toán 6
Các câu hỏi tương tự
Hãy so sánh : \(\dfrac{1}{6}+\dfrac{1}{12}+\dfrac{1}{20}+\dfrac{1}{30}+\dfrac{1}{42}+...+\dfrac{1}{9900}\)với \(\dfrac{1}{2}\)
Tính:
a, \(\left(\dfrac{1}{2}+1\right).\left(\dfrac{1}{3}+1\right).\left(\dfrac{1}{4}+1\right)...\left(\dfrac{1}{99}+1\right)\)
b, \(\left(\dfrac{1}{2}-1\right).\left(\dfrac{1}{3}-1\right).\left(\dfrac{1}{4}-1\right)...\left(\dfrac{1}{100}-1\right)\)
c, \(C=\dfrac{4}{30}+\dfrac{4}{70}+\dfrac{4}{126}+...+\dfrac{4}{798}\)
Tìm x biết :
\(2x+\dfrac{7}{6}+\dfrac{13}{12}+\dfrac{21}{20}+\dfrac{31}{30}+\dfrac{43}{42}+\dfrac{57}{56}+\dfrac{73}{72}+\dfrac{91}{90}=10\)
bài 1 : so sánh :
a) dfrac{23}{21}vàdfrac{21}{23}
b)dfrac{19}{26}và dfrac{21}{25}
bài 2 : sắp sếp các phân số sau từ bé đến lớn :
a)dfrac{7}{36};dfrac{24}{36};dfrac{13}{36};dfrac{1}{36};dfrac{43}{36};dfrac{36}{36}
b)dfrac{-3}{10};dfrac{-31}{100};dfrac{-297}{1000};dfrac{10000}{-3056}
c)dfrac{13}{20};dfrac{7}{20};dfrac{9}{4};dfrac{2}{5};dfrac{1}{2}
d)dfrac{13}{21};dfrac{152}{17};dfrac{13}{17};dfrac{-5}{21}
e)dfrac{-1}{2};dfrac{3}{-4};dfrac{-2}{3};dfrac{4}{-5}
Đọc tiếp
bài 1 : so sánh :
a) \(\dfrac{23}{21}\)và\(\dfrac{21}{23}\)
b)\(\dfrac{19}{26}\)và \(\dfrac{21}{25}\)
bài 2 : sắp sếp các phân số sau từ bé đến lớn :
a)\(\dfrac{7}{36};\dfrac{24}{36};\dfrac{13}{36};\dfrac{1}{36};\dfrac{43}{36};\dfrac{36}{36}\)
b)\(\dfrac{-3}{10};\dfrac{-31}{100};\dfrac{-297}{1000};\dfrac{10000}{-3056}\)
c)\(\dfrac{13}{20};\dfrac{7}{20};\dfrac{9}{4};\dfrac{2}{5};\dfrac{1}{2}\)
d)\(\dfrac{13}{21};\dfrac{152}{17};\dfrac{13}{17};\dfrac{-5}{21}\)
e)\(\dfrac{-1}{2};\dfrac{3}{-4};\dfrac{-2}{3};\dfrac{4}{-5}\)
a)Chứng minh \(\dfrac{1}{2}< \dfrac{1}{51}+\dfrac{1}{52}+\dfrac{1}{53}+..........+\dfrac{1}{100}< 1\)
b)So sánh A=\(\dfrac{10^{19}+1}{10^{20}+1}\) B=\(\dfrac{10^{20}+1}{10^{21}+1}\)
So sánh: A=\(\dfrac{1}{2}+\dfrac{1}{11}+\dfrac{1}{12}+\dfrac{1}{13}+\dfrac{1}{31}+\dfrac{1}{32}+\dfrac{1}{33}\)với 0,9
I. tính
1. \(\dfrac{1}{2}+\dfrac{1}{6}+\dfrac{1}{12}+\dfrac{1}{20}+\dfrac{1}{30}\)
2.\(\dfrac{2}{15}+\dfrac{2}{35}+\dfrac{2}{63}+\dfrac{2}{99}+\dfrac{2}{143}\)
II. tìm x
\(1\dfrac{3}{5}+\left(\dfrac{\dfrac{2}{171}}{\dfrac{5}{171}}+\dfrac{\dfrac{2}{373}}{\dfrac{5}{373}}\right)X=\dfrac{16}{5}\)
Tính nhanh:
P=\(\dfrac{3}{2}-\dfrac{5}{6}+\dfrac{7}{12}-\dfrac{9}{20}+\dfrac{11}{30}-\dfrac{13}{42}+\dfrac{15}{56}-\dfrac{17}{72}\)
Làm giúp mình ngay bây giờ nhé .
bài 1 : Chứng minh :
a) \(\dfrac{1.3.5...39}{21.22.23...40}=\dfrac{1}{2^{20}}\)
b) \(\dfrac{1.3.5...\left(2n-1\right)}{\left(n+1\right)\left(n+2\right)...2n}=\dfrac{1}{2^n}\)