A =( 2/39 −1/15 −2/153 : 1/34 +3/20 −3/26) :( 1+2/71 −5/121: 65/121 −26/71 −13 )
B = ( 112/13.20 +112/20.27 +112/27.34 +...+112/62.69 ) :( −5/9.13 −7/9.25 −13/19.25 −31/19.69 )
mấy cái dấu / hay : là thay cho phân số
Rút gọn
A = \(\frac{\frac{2}{39}-\frac{1}{15}-\frac{2}{153}}{\frac{1}{34}+\frac{3}{20}-\frac{3}{26}}\): \(\frac{1+\frac{2}{71}-\frac{5}{121}}{\frac{65}{121}-\frac{26}{71}-13}\)
B = ( \(\frac{112}{13.20}+\frac{112}{20.27}+\frac{112}{27.34}+...+\frac{112}{62.69}\)) :( \(-\frac{5}{9.13}-\frac{7}{9.25}-\frac{13}{19.25}-\frac{31}{19.69}\))
tính :
C=(112/13.20+112/20.27+112/27.34+...+112/62.69):(-5/9.13-7/9.25-13/19.25-31/19.69)
a.(112/13.20 + 112/ 20.27 + 112/ 27.34 + ... +112/62.69 ) : ( -5/9.13 -7/ 9.25 - 13/19.25 - 31/19.69)
Tính bằng cách hợp lí. Ai giải nhanh mình tick cho
A=112/13.20 + 112/20.27 +... +112/62.69):(-5/9.13 - -7/9.25 - 13/19.25 - 31/19.69)
\(\left(\frac{112}{13.20}+\frac{112}{20.27}+\frac{112}{27.34}+....+\frac{112}{62.69}\right):\left(-\frac{5}{9.13}-\frac{7}{9.25}-\frac{13}{19.25}-\frac{31}{19.69}\right)\)
B=\(\left(\frac{112}{13.20}+\frac{112}{20.27}+\frac{112}{27.34}+.........+\frac{112}{62.69}\right):\left(\frac{-5}{9.13}-\frac{7}{9.25}-\frac{13}{19.25}-\frac{31}{19.69}\right)\)
\(=\left[16\cdot\left(\dfrac{1}{13}-\dfrac{1}{20}+\dfrac{1}{20}-\dfrac{1}{27}+...+\dfrac{1}{62}-\dfrac{1}{69}\right)\right]:\dfrac{-112}{897}\)
\(=16\left(\dfrac{1}{13}-\dfrac{1}{69}\right)\cdot\dfrac{-897}{112}\)
\(=-\dfrac{897}{7}\cdot\dfrac{56}{897}=-8\)
Tính hợp lí : (112/13.20+112/20.27+...+112/62.69):(-5/9.13-7/9.25-13/19.25-31/19.69)
Tính :
\(\left(\dfrac{112}{13.20}+\dfrac{112}{20.27}+\dfrac{112}{27.34}+...+\dfrac{112}{62.69}\right):\left(-\dfrac{5}{9.13}-\dfrac{7}{9.25}-\dfrac{13}{19.25}-\dfrac{31}{19.69}\right)\)
Tính hợp lí : (112/13.20+112/20.27+...+112/62.69):(-5/9.13-7/9.25-13/19.25-31/19.69)