Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Bài 1:
a, (-6) . (-5) . (-4) = 30 . (-4) = -120
b,(-3-5) . (5-3) = (-8) .2 = -16
c,(-3+6) .(-4) = 2 .(-4) = -8
d,(-5-13):(-6) = (-18) : (-6) = 3
bạn ơi,mình vừa kiểm tra lại thì câu c bạn làm sai nha!
Câu c,(-3+6).(-4)
=3.(-4)
=-12
Mình làm mẫu 1 bài rùi bạn tự giải những bài còn lại nha
1, 7A = 7+7^2+7^3+....+7^2008
6A = 7A - A = (7+7^2+7^3+....+7^2008)-(1+7+7^2+....+7^2007) = 7^2008-1
=> A = (7^2008-1)/6
Tk mk nha
\(A=1+7+7^2+7^3+...+7^{2007}\)
\(\Rightarrow7A=7+7^2+7^3+7^4+...+7^{2008}\)
\(\Rightarrow7A-A=\left(7+7^2+7^3+...+7^{2008}\right)-\left(1+7+7^2+...+7^{2007}\right)\)
\(\Rightarrow6A=7^{2008}-1\)
\(\Rightarrow A=\frac{7^{2008}-1}{6}\)
a) (–4) . (–5) . (–6) = [(- 4).(- 5)].(- 6) = 20.(- 6) = -(20.6) = -120
b) (–3 + 6) . (–4) = 3 . (–4) = – (3 . 4) = –12
c) (–3 –5) . (–3 + 5) = (–8) .2 = –(8 . 2) = –16;
d) (–5 – 13) : (–6) = (–18) : (–6) = 18 : 6 = 3.
a) \(\left(-4\right).\left(-5\right).\left(-6\right)=20.\left(-6\right)=\left(-120\right)\)
b) \(\left(-3+6\right).\left(-4\right)=3.\left(-4\right)=-12\)
c) \(\left(-3-5\right).\left(-3+5\right)=\left(-8\right).2=\left(-16\right)\)
d) \(\left(-5-13\right):\left(-6\right)=\left(-18\right):\left(-6\right)=3\)
a; - \(\dfrac{10}{13}\) + \(\dfrac{5}{17}\) - \(\dfrac{3}{13}\) + \(\dfrac{12}{17}\) - \(\dfrac{11}{20}\)
= - (\(\dfrac{10}{13}\) + \(\dfrac{3}{13}\)) + (\(\dfrac{5}{17}\) + \(\dfrac{12}{17}\)) - \(\dfrac{11}{20}\)
= - 1 + 1 - \(\dfrac{11}{20}\)
= 0 - \(\dfrac{11}{20}\)
= - \(\dfrac{11}{20}\)
b; \(\dfrac{3}{4}\) + \(\dfrac{-5}{6}\) - \(\dfrac{11}{-12}\)
= \(\dfrac{9}{12}\) - \(\dfrac{10}{12}\) + \(\dfrac{11}{12}\)
= \(\dfrac{10}{12}\)
= \(\dfrac{5}{6}\)
c; [13.\(\dfrac{4}{9}\) + 2.\(\dfrac{1}{9}\)] - 3.\(\dfrac{4}{9}\)
= [\(\dfrac{52}{9}\) + \(\dfrac{2}{9}\)] - \(\dfrac{4}{3}\)
= \(\dfrac{54}{9}\) - \(\dfrac{4}{3}\)
= \(\dfrac{14}{3}\)
a) = -120
b) = 3 x (-4)
= -12
c) = -8 x 2
= -16
d) = -18 : (-6)
= 3
`#` `\text{dkhanhqlv}`
`a)-2+(-5/8)`
`=-2-5/8`
`=-16/8-5/8`
`=-21/8`
`b)5+(-3/4)`
`=5-3/4`
`=20/4-3/4`
`=17/4`
`c)4/3+(-6)`
`=4/3-6`
`=4/3-18/3`
`=-14/3`
`d)-8-2/7`
`=-56/7-2/7`
`=-58/7`
`e)-3/5-9`
`=-3/5-45/5`
`=-48/5`
`g)6-(-4/13)`
`=6+4/13`
`=78/13+4/13`
`=82/13`
\(a,\left(-2\right)-\dfrac{5}{8}=-\dfrac{21}{8}\)
\(b,5+\left(-\dfrac{3}{4}\right)=5-\dfrac{3}{4}=\dfrac{20}{4}-\dfrac{3}{4}=\dfrac{17}{4}\)
\(c,\dfrac{4}{3}+\left(-6\right)=\dfrac{4}{3}-6=-\dfrac{14}{3}\)
\(d,\left(-8\right)-\dfrac{2}{7}=-\dfrac{58}{7}\)
\(e,-\dfrac{3}{5}-9=-\dfrac{48}{5}\)
\(g,6-\left(-\dfrac{4}{13}\right)=6+\dfrac{4}{13}=\dfrac{82}{13}\)
a) ( - 4 ) . ( - 5 ) . ( - 6 )=( - 120)
b) ( - 3 + 6 ) . ( - 4 )
= - 12
c) ( - 3 - 5 ) . ( - 3 + 5 )= 0
d) ( - 5 - 13 ) : ( - 6 )=3
Câu hỏi tương tự Đọc thêm Báo cáo\(a.\left(-4\right)\left(-5\right)\left(-6\right)=20\left(-6\right)=-120\)
\(b.\left(-3+6\right)\left(-4\right)=3\left(-4\right)=-12\)
\(c.\left(-3-5\right)\left(-3+5\right)=\left(-8\right)\left(2\right)=-16\)
\(d.\left(-5-13\right)\div\left(-6\right)=\left(-18\right)\div\left(-6\right)=3\)