5. (-3)2-14. (-8) + (-40)
(-50+19+143)-(-79+25+48)
tinh nhanh
3) (187 -23) – (20 – 180)
4) (-37 – 17). (-9) + 35. (-9 – 11)
5) (-50 +19 +143) – (-79 + 25 + 48)
6) (-8).25.(-2). 4. (-5).125
7) 3784 + 23 – 3785 – 15
7: =-1+8=7
6: \(=-\left(8\cdot125\right)\cdot\left(2\cdot5\right)\cdot\left(25\cdot4\right)=-1000000\)
5: =-50+19+143+79-25-48
=-75+98+95
=23+95
=118
4: =37x9+17x9-35x9-35x11
=18+153-385
=-214
tinh nhanh
3) (187 -23) – (20 – 180)
4) (-37 – 17). (-9) + 35. (-9 – 11)
5) (-50 +19 +143) – (-79 + 25 + 48)
6) (-8).25.(-2). 4. (-5).125
7) 3784 + 23 – 3785 – 15
3: =187-23-20+180
=367-43
=324
4: \(=37\cdot9+17\cdot9-35\cdot9-35\cdot11=19\cdot9-385\)
\(=171-385=-214\)
5: =-50+19+143+79-25-48
=-75+94+95
=20+94
=114
3 ; 324
4 ; -214
5 ; 118
6 ; - 1 000 000
7 ; 7
học tốt
Bài 2: Tính hợp lí
1) 125.(-24) + 24.225
2) 512.(2 – 128) – 128. (-512)
3) (187 -23) – (20 – 180)
4) (-37 – 17). (-9) + 35. (-9 – 11)
5) (-50 +19 +143) – (-79 + 25 + 48)
6) (-8).25.(-2). 4. (-5).125
7) 3784 + 23 – 3785 – 15
8) 215 +(-38) – (-58) –15
9) 5.(-3)2 –14.(-8)+(-40)
10) 215 + (-38) – (- 58) + 90 – 852)
Bài 3*: Tìm các cặp số nguyên (x;y) thỏa mãn xy2 + 2x – y2 =
1) 125.(-24) + 24.225.
\(=24\left(-125+225\right)=24.100=2400.\)
2) 512.(2 – 128) – 128. (-512).
\(=512\left(2-128+128\right)=512.2=1024.\)
(-50+19+143)-(-79+25+48)
(-50 + 19 + 143)-(-79 + 25 +48)
= (-31 + 143 ) - (-54 + 48 )
= 112 - (-6)
= 112 + 6
= 118
\(\left(-50+19+143\right)-\left(-79+25+48\right)\)
\(=-50+19+143+79-25-48\)
\(=-50-25+\left(79-48+19\right)+143\)
\(=-75+50+143\)
\(=-25+143\)
\(=118\)
tính : (-50+19-143) - (-79+25+48)
tính hợp lý
a)5.(-3)^2-14.(-8)+(-40)
b)31-[26-(209+35)]
c)237+26-(209+26)
d)21+22+23+24-11-12-13-14
e)(-12).46-12.54
g)(-8).25.(-2).4.(-5).125
h)(-50+19+143)-(-79+25+48)
i)(-37-17).(-9)+35.(-9-11)
k)512.(2-128)-128.(-512)
l)160:{|-17|+[3^2.5-(14+2^11:2^8)]
m)|-6|+(-17)+|-4|+(-3)
n)5^6:5^3-5^0.5^1.5^2
o)100:{31-[24:(18-7.2)]}
k)
Mình lớp 4 mà bạn
Với lại là bằng :
6''675
7785.,77
664'87'9776''8
[-50+19+143]-[-79+25+48]=
[-50+19+143]-[-79+25+48]=118
tinh
(-50 + 19 + 143) – (-79 + 25 + 48)
(-50+19+143)-(79+25+48) giúp mình với
\(\left(-50+19+143\right)-\left(79+25+48\right)\)
\(=-50+19+143-79-25-48\)
\(=-31+143-79-25-48\)
\(=112-79-25-48\)
\(=33-25-48\)
\(=8-48\)
\(=-40\)
\(\left(-50+19+143\right)-\left(79+25+48\right)\)
\(=-50+19+143-79-25-48\)
\(=-34+64-\left(-23\right)\)
\(=53\)
hok tốt