Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) 23 - ( - 35 ) = 23 + 35 = 58
b) ( - 145 ) - ( - 254 ) = ( - 145) + 254 = 109
c) \([\left(-3\right)-4]+8=\left(-7\right)+8=1\)
d) 0 - ( - 2 ) + 6 = 2 + 6 = 8
\(B=\frac{1}{1\cdot2\cdot3}+\frac{1}{2\cdot3\cdot4}+\frac{1}{3\cdot4\cdot5}+\frac{1}{18\cdot19\cdot20}\)
\(B=\frac{1}{2}\left(\frac{2}{1\cdot2\cdot3}+\frac{2}{2\cdot3\cdot4}+\frac{2}{3\cdot4\cdot5}+\frac{2}{18\cdot19\cdot20}\right)\)
\(B=\frac{1}{2}\left(\frac{1}{1\cdot2}-\frac{1}{2\cdot3}+\frac{1}{2\cdot3}-\frac{1}{3\cdot4}+\frac{1}{3\cdot4}-\frac{1}{4\cdot5}+...+\frac{1}{18\cdot19}-\frac{1}{19\cdot20}\right)\)
\(B=\frac{1}{2}\left(\frac{1}{1\cdot2}-\frac{1}{19\cdot20}\right)\)
\(B=\frac{1}{2}\cdot\frac{189}{380}=\frac{189}{760}\)
\(C=\frac{52}{1\cdot6}+\frac{52}{6\cdot11}+\frac{52}{11\cdot16}+...+\frac{52}{31\cdot36}\)
\(C=\frac{52}{5}\left(\frac{5}{1\cdot6}+\frac{5}{6\cdot11}+\frac{5}{11\cdot16}+...+\frac{6}{31\cdot36}\right)\)
\(C=\frac{52}{5}\left(1-\frac{1}{6}+\frac{1}{6}-\frac{1}{11}+\frac{1}{11}-\frac{1}{16}+...+\frac{1}{31}-\frac{1}{36}\right)\)
\(C=\frac{52}{5}\cdot\left(1-\frac{1}{36}\right)\)
\(C=\frac{91}{9}\)
a.12-6=6
b.23-(-35)=23-35=-12
c.(-145)-(-254)= - (145+254)=-399
a. 12-6 =6
b. 23-(-35)=23+35=58
c.(-145)-(-254)=(-145)+254=254-145=109
1/ -7264 + (1543 + 7264)
=-7264 + 1543 + 7264=1543
2/ (144 – 97) – 144
=144-97-144=-97
3/ (-145) – (18 – 145)(Vì có dấu trừ ở trước ngoặc nên p đổi dấu)
=-145-18+145=-18
4/ 111 + (-11 + 27)
=111-11+27=137
a)\(\frac{7}{1}.\frac{5}{9}.\frac{11}{35}=\frac{7.5.11}{9.5.7}=\frac{11}{9}\)
b) \(\frac{3}{5}.\frac{4}{23}.\frac{5}{6}=\frac{3.2.2.5}{5.23.3.2}=\frac{2}{23}\)
c) \(\frac{5}{2}.\frac{7}{4}.\frac{2}{7}=\frac{5.7.2}{2.7.4}=\frac{5}{4}\)
d) \(\frac{19}{23}.\frac{12}{17}.\frac{85}{24}=\frac{19.12.5.17}{23.17.12.2}=\frac{19.5}{23.2}=\frac{95}{46}\)
Tính
A. \(\frac{7}{1}x\frac{5}{9}x\frac{11}{35}=\frac{7x5x11}{1x9x35}=\frac{11}{9}\)
B. \(\frac{3}{5}x\frac{4}{23}x\frac{5}{6}=\frac{3x4x5}{5x23x6}=\frac{2}{23}\)
C. \(\frac{5}{2}x\frac{7}{4}x\frac{2}{7}=\frac{5x7x2}{2x4x7}=\frac{35}{28}\)
D. \(\frac{19}{23}x\frac{12}{17}x\frac{85}{24}=\frac{19x12x85}{23x17x24}=\frac{4845}{2346}\)
a) 12 - 6 = 6
b) 23 - (-35) = 58
c) = 109
Bài 2: a) = 1
b) -3
c) = 8
Bạn tick cho mik cái nha!!! <3 <3 <3