1.So sánh

a.\(\dfrac{21}{52}\)và\(\dfrac{-213}{523}\)

b.\(\dfrac{22}{35}\)và\(\dfrac{103}{17}\)

c.\(\dfrac{-2525}{4949}\)và\(\dfrac{-131313}{373737}\)

Tính nhanh

1/3 - 3/4 - 3/5 + 1/64 - 2/9 - 1/36 + 1/15

Tính nhanh

1/5-3/7+5/9-2/11+7/13-9/16-7/13+2/11-5/9+3/7-1/5

1) Tính : a) \(\left(\dfrac{-5}{11}\right)\) .\(\dfrac{7}{15}\) . \(\left(\dfrac{11}{-5}\right)\) .(-30) b) \(\left(\dfrac{11}{12}:\dfrac{33}{16}\right)\). \(\dfrac{3}{5}\) c) \(\dfrac{-7}{15}\).\(\dfrac{5}{8}\).\(\dfrac{15}{-7}\). (-16) d) \(\left(-\dfrac{1}{2}\right)\). \(3\dfrac{1}{5}\)+ \(\left(-\dfrac{1}{2}\right)\).\(-2\dfrac{1}{5}\)

Tính nhanh:

\(\left(\dfrac{-3}{7}+\dfrac{4}{11}\right):\dfrac{7}{11}+\left(\dfrac{-4}{7}+\dfrac{7}{11}\right):\dfrac{7}{11}\)

Các bn giúp mk vs nha

\(\dfrac{6^3+3\cdot6^2+3^3}{-13}\)

1.\(\dfrac{-1}{4}-\dfrac{3}{4}:x=\dfrac{-11}{36}\)

2.\(\left(-1\dfrac{1}{5}+x\right):\left(-3\dfrac{3}{5}\right)=\dfrac{-7}{4}+\dfrac{1}{4}:\dfrac{1}{8}\)

a) \(\dfrac{-2}{7}.\dfrac{21}{8}\) b) 0.24.\(\dfrac{-15}{4}\)

c) (-2).\(\left(\dfrac{-7}{12}\right)\) d) \(\left(\dfrac{-3}{25}\right):6\)

Tìm a,b biết

a+b=a*b=a/b

Cho tam giác ABC cân tại A.Gọi M là trung điểm cạnh BC.

a,C/m tam giác ABM=tam giác ACM

b,Từ M vẽ MH vuông góc AB và MK vuông góc AC.C/m BH=CK

C,Từ B vẽ BP vuông góc AC,BP cắt MH tại I.C/m tam giác IBM cân