Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
sai vì mới nhìn đã bit là toàn số chẵn nhân nhau mà bằng 1 số lẻ
Sai, vì các số hạng trong tổng đều là số chẵn nên kết quả là chẵn
\(\dfrac{-2}{3}\cdot\dfrac{5}{7}+\dfrac{5}{7}:\dfrac{3}{4}-1=\dfrac{-2}{3}\cdot\dfrac{5}{7}+\dfrac{5}{7}\cdot\dfrac{4}{3}-1=\left(\dfrac{-2}{3}+\dfrac{4}{3}\right)\cdot\dfrac{5}{7}-1=\dfrac{2}{3}\cdot\dfrac{5}{7}-1=\dfrac{10}{21}-1=-\dfrac{11}{21}\)
−2 / 3⋅5 / 7+5 / 7:3 / 4−1=−2 / 3⋅5 / 7+5 / 7⋅4 / 3−1=(−2 / 3+4 / 3)⋅5 /. 7−1=2 / 3⋅5 / 7−1=10 / 21−1=−11 / 21
nha
\(\dfrac{4}{5}\)+\(\dfrac{-5}{4}\)=\(\dfrac{0}{4}\)
\(\dfrac{-1}{3}\)+\(\dfrac{2}{5}-\dfrac{5}{6}\)=\(\dfrac{-10}{30}+\dfrac{12}{30}-\dfrac{25}{30}\)=\(\dfrac{-23}{30}\)
\(\dfrac{2}{3}-\dfrac{5}{7}.\dfrac{14}{25}\)=\(\dfrac{2}{3}-\dfrac{2}{5}\)=\(\dfrac{10}{15}-\dfrac{6}{15}\)=\(\dfrac{4}{15}\)
a. 115-(19-24)
= 115-(-5)
= 120
b. -25+7.(4-12)
= -25+7.(-8)
= -25+(-56)
= -81
a, = 20 .(-4) + 31 . (-20)
= -80 - 620 = -700
b, = -18 . 31 - 28 .(-24)
= -558 + 672 = 114
a )
= 20 x (-4) + 31 x ( -20 )
= ( -20 ) x 4 + 31 x ( - 20 )
= ( - 20 ) x ( 4 + 31 )
= ( - 20 0 x 35
= -700
b)
=-18 x 31 - 28 x -24
=-558 - -672
=(-558) +( 672)
= 114
a)=-7/21+8/24
=-1/3+1/3
=0
b)=-3/5.(2/7+5/7)+23/5
=-3/5.7/7+23/5
=-3/5.1+23/5
=-3/5+23/5
=20/5=4
c)=75/100-11/2+5/10:5/12+1/4
=3/4-11/2+1/2:5/12+1/4
=3/4+-11/2+1/2.12/5+1/4
=3/4+-22/4+6/5+1/4
=-19/4+6/5+1/4
=(-19/4+1/4)+6/5
=-18/4+6/5
=-9/2+6/5
=-45/10+12/10
=-23/10
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. \(\frac{19}{23}x\frac{12}{17}x\frac{85}{24}=\frac{19x12x85}{23x17x24}=\frac{4845}{2346}\)
-1/2 + -7/24 + 19/24
=-19/24 + 19/24 =0
-1/2 + -7/24 + 19/24
=-12/24 + -7/24 + 19/24
=-19/24 + 19/24
=0