Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
31.(-18)+31.(-81)-31
= 31.[(-18)+(-81)]
= 31.(-100)
= -3100
135.(171-123)-171.(135-123)
=(135.171-135.123)-(171.135-171.123)
=135.171-135.123-171.135+171.123
=(135.171-171.135)-(135.123-171.123)
=0-123.(135-171)
=0-(-4428)=4428
K)-(-2009+97)-74.(-18)+74.(-118)-2009-3
=2009-97-74.(-18)+74.(-118)-2009-3
=2009-97-74.[(-18)+118]-2009-3
=(2009-2009)-74.100-(97+3)
=0-7400-100
=-7400-100=-7500
Mik bổ sung thêm nha
jup đi mak
ai bt lm hộ cái zùi trả công cho!!!!!!!1
a,(38-129+43)-(43+38)=38-129+43-43-38=(38-38)+(43-43)-129=-129
b,-144-[29-(+144)-(-144)=-144-29+144-144=(144-144)-29-144=-173
c)48+|48-174|+(-74)=18+126-74=70
d)(-123+77)-(277-23-123)=-123+77-277+23+123=(-123+123)+(77-277)+23=-200+23=-177
e)-(-57-159)+(43-169)=57+129+43-169=(57+43)+(129-169)=100-40=60
Chúc bạn học tốt( sai chỗ nào cho mjk sr nka??) k cho mjk nka
Câu 1:
a) Ta có: 2n+1 là số lẻ∀n
⇒\(\left(-1\right)^{2n+1}=-1\)
Ta có: \(\left(-25\right)\cdot21\cdot\left(-2\right)^2\cdot\left(-\left|-3\right|\right)\cdot\left(-1\right)^{2n+1}\)
\(=-25\cdot21\cdot4\cdot\left(-3\right)\cdot\left(-1\right)\)
\(=75\cdot84\cdot\left(-1\right)\)
\(=-6300\)
b) Ta có: \(\left(-5\right)^3\cdot67\cdot\left(-\left|-2^3\right|\right)\cdot\left(-1\right)^{2n}\)
\(=-125\cdot67\cdot\left(-8\right)\)
\(=1000\cdot67=67000\)
c) Ta có: \(35\cdot18-5\cdot7\cdot28\)
\(=35\cdot18-35\cdot28\)
\(=35\cdot\left(18-28\right)=35\cdot\left(-10\right)=-350\)
d) Ta có: \(24\cdot\left(16-5\right)-16\cdot\left(24-5\right)\)
\(=24\cdot16-24\cdot5-24\cdot16+16\cdot5\)
\(=-24\cdot5+16\cdot5\)
\(=5\cdot\left(-24+16\right)=5\cdot\left(-8\right)=-40\)
e) Ta có: \(29\cdot\left(19-13\right)-19\cdot\left(19-13\right)\)
\(=6\cdot\left(29-19\right)=6\cdot10=60\)
g)Sửa đề: \(31\cdot\left(-18\right)+31\cdot\left(-81\right)-31\)
Ta có: \(31\cdot\left(-18\right)+31\cdot\left(-81\right)-31\)
\(=31\cdot\left(-18-81-1\right)\)
\(=31\cdot\left(-100\right)=-3100\)
h) Ta có: \(\left(-12\right)\cdot47+\left(-12\right)\cdot52+\left(-12\right)\)
\(=-12\cdot\left(47+52+1\right)\)
\(=-12\cdot100=-1200\)
k) Ta có: \(13\cdot\left(23+22\right)-3\cdot\left(17+28\right)\)
\(=13\cdot45-3\cdot45\)
\(=45\cdot\left(13-3\right)=45\cdot10=450\)
m) Ta có: \(-48+48\cdot\left(-78\right)+48\cdot\left(-21\right)\)
\(=48\cdot\left(-1-78-21\right)\)
\(=48\cdot\left(-100\right)=-4800\)
n) Ta có: \(135\cdot\left(171-123\right)-171\cdot\left(135-123\right)\)
\(=135\cdot171-135\cdot123-171\cdot135+171\cdot123\)
\(=123\cdot\left(-135+171\right)=123\cdot36=4428\)
a) ( 123-27) +( 27+13-123)
= 123-27+27+27+13-123
= 123+13-123
= 13
b) (2020 -119 + 29) -(-119+29)
=2020-119+29+119-29
=2020+(119-119)+(29-29)
=2020
a) (123 - 27) +(27 + 13 - 123 )
= 123 - 27 +27 + 13 - 123
= 123- 123 -27 +27 +13
= 13
b)( 2020 - 119 +29 ) - (-119 +29 )
=2020 - 119 + 29 + 119 -29
= 2020 -119 + 119 + 29 - 29
=2020
123 . 19 + 123 . 52 + 123 . 29
= 123 . ( 19 + 52 + 29 )
= 123 . 100
= 12300
123( 19 + 52 + 29)
= 123 . 100
= 12300