a,x9 ×1/x10
b,(-1/81)6:(1/21)3
C,754:253
D,5015×1318
257×2615×516
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) \(\dfrac{-3}{20}\) + \(\dfrac{-7}{4}\) =\(\dfrac{-3}{20}\) + \(\dfrac{-35}{20}\) = -2
b) 6 và \(\dfrac{2}{3}\) - 4 và \(\dfrac{2}{3}\) = 2
c) \(\dfrac{-3}{10}\) + \(\dfrac{7}{12}\) = \(\dfrac{-18}{60}\) + \(\dfrac{35}{60}\) =\(\dfrac{17}{60}\)
d) \(\dfrac{35}{-9}\) . \(\dfrac{81}{7}\) = \(\dfrac{-35}{9}\) . \(\dfrac{81}{7}\) = 45
e) \(\dfrac{-2}{5}\) - \(\dfrac{-3}{4}\) = \(\dfrac{-8}{20}\) - \(\dfrac{-15}{20}\) = \(\dfrac{-8}{20}\) + \(\dfrac{15}{20}\) =\(\dfrac{7}{20}\)
f) \(\dfrac{5}{23}\) . \(\dfrac{7}{26}\) + \(\dfrac{5}{23}\) .\(\dfrac{9}{26}\) = \(\dfrac{5}{23}\) . ( \(\dfrac{7}{26}\) + \(\dfrac{9}{26}\) )= \(\dfrac{5}{23}\) . \(\dfrac{8}{13}\) = \(\dfrac{40}{299}\)
g) \(\dfrac{-3}{12}\) : \(\dfrac{4}{15}\) =\(\dfrac{-3}{12}\) . \(\dfrac{15}{4}\) =\(\dfrac{-5}{8}\)
h) 1 và \(\dfrac{1}{6}\) - 3 và \(\dfrac{1}{3}\) =\(\dfrac{7}{6}\) -\(\dfrac{10}{3}\) = \(\dfrac{-13}{6}\)
i) \(\dfrac{-2}{5}\) . (-3) + \(\dfrac{3}{8}\) . \(\dfrac{4}{-10}\) =(\(\dfrac{-2}{5}\) .\(\dfrac{-4}{10}\)) + [(-3) . \(\dfrac{3}{8}\)
= \(\dfrac{4}{25}\) + \(\dfrac{-9}{8}\) = \(\dfrac{32}{200}\) + \(\dfrac{-225}{200}\) = \(\dfrac{-193}{200}\)
j) \(\dfrac{-13}{17}\) + (\(\dfrac{13}{-21}\) + \(\dfrac{-4}{17}\) )
= ( \(\dfrac{-13}{17}\) + \(\dfrac{-4}{17}\) )+\(\dfrac{-13}{21}\)
= -1+\(\dfrac{-13}{21}\)
= \(\dfrac{-21}{21}\) + \(\dfrac{-13}{21}\) = \(\dfrac{-34}{21}\)
Khôi nguyễn
Bài 2:
c: \(y:312=345:5\)
\(\Leftrightarrow y:312=69\)
hay \(y=21528\)
d: \(918670-y=251\cdot142\)
\(\Leftrightarrow y=91867-35642=56225\)
a: \(C=\dfrac{-1}{2}:\dfrac{-2}{3}:\dfrac{-3}{4}\)
\(=\dfrac{-1}{2}\cdot\dfrac{3}{-2}\cdot\dfrac{4}{-3}\)
\(=-\dfrac{4}{4}=-1\)
b: \(D=\dfrac{-6}{5}:\dfrac{-5}{4}:\dfrac{-4}{3}\)
\(=-\dfrac{6}{5}\cdot\dfrac{4}{5}\cdot\dfrac{3}{4}\)
\(=\dfrac{-18}{25}\)
c: \(\dfrac{4}{20}+\dfrac{16}{42}+\dfrac{6}{15}+\dfrac{-3}{5}+\dfrac{2}{21}+\dfrac{-10}{21}+\dfrac{3}{20}\)
\(=\left(\dfrac{4}{20}+\dfrac{-3}{5}+\dfrac{6}{15}\right)+\left(\dfrac{16}{42}+\dfrac{2}{21}-\dfrac{10}{21}\right)+\dfrac{3}{20}\)
\(=\left(\dfrac{1}{5}-\dfrac{3}{5}+\dfrac{2}{5}\right)+\left(\dfrac{8}{21}+\dfrac{2}{21}-\dfrac{10}{21}\right)+\dfrac{3}{20}\)
\(=\dfrac{3}{20}\)
d: \(\dfrac{42}{46}+\dfrac{250}{186}+\dfrac{-2121}{2323}+\dfrac{-125125}{143143}\)
\(=\dfrac{21}{23}+\dfrac{125}{93}+\dfrac{-21}{21}+\dfrac{-125}{143}\)
\(=\dfrac{125}{93}-\dfrac{125}{143}=\dfrac{6250}{13299}\)
\(5015^{2^{0^{1^3}}}=5015^{2^{0^1}}=5015^{2^0}=5015^1=5015\)
a) ( 72 - 8x9 ) : ( 20 + 21 + 22 + 23 + 24 + 25 )
= ( 72 - 72 ) : ( 20 + 21 + 22 + 23 + 24 + 25 )
= 0 : ( 20 + 21 + 22 + 23 + 24 + 25 )
= 0
b) ( 500 x 9 - 250 x 18 ) x ( 1 + 2 + 3 + ... + 9 )
= ( 250 x 2 x 9 - 250 x 18 ) x ( 1 + 2 + 3 + ... + 9 )
= ( 250 x 18 - 250 x 18 ) x ( 1 + 2 + 3 + ... + 9 )
= 0 x ( 1 + 2 + 3 + ... + 9 )
= 0
c ) ( 11 + 13 + 15 + ... + 19 ) x ( 6 x 8 - 48 )
= ( 11 + 13 + 15 + ... + 19 ) x ( 48 - 48 )
= ( 11 + 13 + 15 + ... + 19 ) x 0
= 0
a) ( 72 - 8x9 ) : ( 20 + 21 + 22 + 23 + 24 + 25 )
= ( 72 - 72 ) : ( 20 + 21 + 22 + 23 + 24 + 25 )
= 0 : ( 20 + 21 + 22 + 23 + 24 + 25 )
= 0
a) \(-x+821+534=499+\left(x-84\right)\)
\(-x-x=499-84-821-534\)
\(-2x=-940\)
\(x=470\)
b) \(x-96=\left(448-x\right)-150\)
\(x+x=448-150+96\)
\(2x=394\)
\(x=197\)
c) \(-\left(754+x\right)=\left(x-12-741\right)-23\)
\(-754-x=x-12-741-23\)
\(-x+x=-12-741-23+754\)
\(0x=2\)
\(x\)ko tồn tại
d) \(\left(6+x\right)-\left(17-21\right)=-25\)
\(6+x-17+21=-25\)
\(x=-25-6+17-21\)
\(x=-35\)
e) \(17-\left(x+2\right)=3\)
\(17-x-2=3\)
\(-x=3-17+2\)
\(-x=-12\)
\(x=12\)
h) \(-10-\left(31-x\right)=40\)
\(-10-31+x=40\)
\(x=40+10+31\)
\(x=81\)
k mk nha bạn
a) \(-x+821+534=499+\left(x-84\right)\)
\(\Leftrightarrow-x+821+534=499+x-84\)
\(\Leftrightarrow821+534-499+84=x+x\)
\(\Leftrightarrow940=2x\)
\(\Leftrightarrow x=\dfrac{940}{2}\)
\(\Leftrightarrow x=470\)
Vậy \(x=470\)
b) \(x-96=\left(448-x\right)-150\)
\(\Leftrightarrow x-96=448-x-150\)
\(\Leftrightarrow x+x=96+448-150\)
\(\Leftrightarrow2x=394\)
\(\Leftrightarrow x=\dfrac{394}{2}\)
\(\Leftrightarrow x=197\)
Vậy \(x=197\)
c) \(- (754 + x) = (x - 12 - 741) - 23\)
\(\Leftrightarrow-754-x=x-12-741-23\)
\(\Leftrightarrow-754+12+741+23=x+x\)
\(\Leftrightarrow22=2x\)
\(\Leftrightarrow x=\dfrac{22}{2}\)
\(\Leftrightarrow x=11\)
Vậy \(x=11\)
d) \((6 + x) - (17 - 21) = -25\)
\(\Leftrightarrow6+x-17+21=-25\)
\(\Leftrightarrow x=-25-6+17-21\)
\(\Leftrightarrow x=-35\)
Vậy \(x=-35\)
e) \(17-\left(x+2\right)=3\)
\(\Leftrightarrow17-x-2=3\)
\(\Leftrightarrow17-2-3=x\)
\(\Leftrightarrow x=12\)
Vậy \(x=12\)
h) \(-10 - (31 - x) = 40\)
\(\Leftrightarrow-10-31+x=40\)
\(\Leftrightarrow x=40+10+31\)
\(\Leftrightarrow x=81\)
Vậy \(x=81\)