2/9+1/3
7/9-1/5
15/35-2/14
3/8 + 5/12
a) 2345 – 1000 : [19 – 2(21 – 18)2] b) 128 – [68 + 8(37 – 35)2] : 4 c) 568 – {5[143 – (4 – 1)2] + 10} : 10 d) 107 – {38 + [7.32 – 24 : 6+(9 – 7)3]}:15 e) 307 – [(180 – 160) : 22 + 9] : 2 f) 205 – [1200 – (42 – 2.3)3] : 40 g) 177 :[2.(42 – 9) + 32(15 – 10)] h) [(25 – 22.3) + (32.4 + 16)]: 5 i) 125(28 + 72) – 25(32.4 + 64) j) 500 – {5[409 – (23.3 – 21)2] + 103} : 15 |
Viết số mũ giùm mình ạ!
a: \(=47-\left[\left(45\cdot16-25\cdot12\right):14\right]\)
\(=47-30=17\)
b: \(=50-\left[6+34\right]\)
=50-40
=10
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).
\(=512\left(2-128+128\right)=512.2=1024.\)
1,(-12).46-12.54
2,3784+23-3785-15
3,(-8).25.(-2).4.(-5).125
4,19.25+9.95+19.30
5,(-50+19+143)-(-79+25+48)
6,(-25).(75-45)-75(45-25)
7,(-37-17).(-9)+35.(-9-11)
8,(187-23)-(20-180)
9,512.(2-128.(-512)
10,17.(-25)+25.21
1/\(\left(-12\right)\cdot46-12\cdot54=\left(-12\right)\cdot46+\left(-12\right)\cdot54\)
\(=\left(-12\right)\cdot\left(46+54\right)=\left(-12\right)\cdot100=-1200\)
2/\(3784+23-3785-15=3785+22-3785-15\)
\(=22-15=7\)
3/\(\left(-8\right)\cdot25\cdot\left(-2\right)\cdot4\cdot\left(-5\right)\cdot125\)
\(=\left[\left(-8\right)\cdot125\right]\cdot\left[25\cdot4\right]\cdot\left[\left(-5\right)\cdot\left(-2\right)\right]\)
\(=\left(-1000\right)\cdot100\cdot10=-1000000\)
4/\(19\cdot25+9\cdot95+19\cdot30=19\cdot\left(25+30\right)+9\cdot95\)
\(=19\cdot55+9\cdot95=95\cdot11+9\cdot95=95\cdot\left(11+9\right)=20\cdot95=1900\)
5/\(\left(-50+19+143\right)-\left(-79+25+48\right)\)
\(=\left(-50\right)+19+143+79-25-48\)
\(=118\)
6/\(\left(-25\right)\cdot\left(75-45\right)-75\cdot\left(45-25\right)\)
\(=\left(-25\right)\cdot30+\left(-25\right)\cdot3\cdot20\)
\(=\left(-25\right)\cdot\left(30+60\right)=\left(-25\right)\cdot90=-2250\)
7/\(\left(-37-17\right)\cdot\left(-9\right)+35\left(-9-11\right)\)
\(=\left(-54\right)\cdot\left(-9\right)+35\cdot\left(-20\right)\)
\(=486+\left(-700\right)=-214\)
8/\(\left(187-23\right)-\left(20-180\right)\)
\(=187-23-20+180=324\)
9/\(512\cdot2-128\cdot\left(-512\right)\)
\(=512\cdot2+128\cdot512=512\cdot\left(2+128\right)\)
\(=512\cdot130=66560\)
10/\(17\cdot\left(-25\right)+25\cdot21\)
\(=17\cdot\left(-25\right)-\left(-25\right)\cdot21=\left(-25\right)\cdot\left(17-21\right)\)
\(=\left(-25\right)\cdot\left(-4\right)=100\)
Chúc bạn học tốt.
k) 2345 – 1000 : [19 – 2(21 – 18)2 ] l) 128 – [68 + 8(37 – 35)2 ] : 4
m) 568 – {5[143 – (4 – 1)2 ] + 10} : 10
n) 107 – {38 + [7.32 – 24 : 6+(9 – 7)3 ]}:15
o) 307 – [(180 – 160) : 22 + 9] : 2
p) 205 – [1200 – (42 – 2.3)3 ] : 40
q) 177 :[2.(42 – 9) + 32 (15 – 10)]
r) [(25 – 2 2 .3) + (32 .4 + 16)]: 5
s) 125(28 + 72) – 25(32 .4 + 64)
giúp mk
s: \(=125\cdot100-25\cdot192\)
\(=12500-4800\)
=7700
Bài 1: Thực hiện phép tính:
a) 3.52 + 15.22 – 26:2
b) 53.2 – 100 : 4 + 23.5
c) 62 : 9 + 50.2 – 33.3
d) 2345 – 1000 : [19 – 2(21 – 18)2]
e) 128 – [68 + 8(37 – 35)2] : 4
f) 568 – {5[143 – (4 – 1)2] + 10} : 10
e: \(=128-\left[68+8\cdot4\right]:4=128-25=103\)
\(a.3.5^2+15.2^2-26:2\) \(b.5^3.2-100:4+2^3.5\)
\(=75+60-13\) \(=250-25+40\)
\(=135+13=148\) \(=265\)
\(c.6^2:9+50.2-3^3.3\) \(d.2345-1000:\left[19-2.\left(21-18\right)^2\right]\)
\(=4+100-81\) \(=2345-1000:\left[19-2.3^2\right]\)
\(=23\) \(=2345-1000:\left[19-18\right]\)
\(=2345-1000:1\)
\(=2345-1000=1345\)
\(e.128-\left[68+8.\left(37-35\right)^2\right]:4\)
\(=128-\left[68+8.2^2\right]:4\)
\(=128-\left[68+32\right]:4\)
\(=128-100:4\)
\(=128-25=103\)
\(f.568-\left\{5.\left[143-\left(4-1\right)^2\right]+10\right\}:10\)
\(=568-\left\{5.\left[143-3^2\right]+10\right\}:10\)
\(=568-\left\{5.134+10\right\}:10\)
\(=568-\left\{670+10\right\}:10\)
\(=568-680:10\)
\(=568-68=500\)
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
1,(-12).46-12.54
2,3784+23-3785-15
3,(-8).25.(-2).4.(-5).125
4,19.25+9.95+19.30
5,(-50+19+143)-(-79+25+48)
6,(-25).(75-45)-75(45-25)
7,(-37-17).(-9)+35.(-9-11)
8,(187-23)-(20-180)
9,512.(2-128)-128.(-512)
10,17.(-25)+25.21
1) (-12).46-12.54
=12.(-46)-12.54
=12.(-46-54)
=12.(-100)=(-1200)
10) 17.(-25)+25.21
= (-17).25+25.21
=25.(-17+21)
=25.4=100
( Mik đọc lướt qua thì thấy hai bài này dễ nên làm, chứ mấy bài kia chưa suy nghĩ gì, bạn tự làm nốt nhé!)
2: \(=\left(3784-3785\right)+\left(23-15\right)=\left(-1\right)+8=7\)
3: \(=-8\cdot25\cdot2\cdot4\cdot5\cdot125\)
\(=-8\cdot125\cdot25\cdot4\cdot2\cdot5=-1000\cdot100\cdot10=-1000000\)
4: \(=19\left(25+9\cdot5+30\right)=19\cdot100=1900\)
5: \(=-50+19+143+79-25-48\)
\(=\left(-50-25+79\right)+143+19-48\)
=54+143-29
=143+25=168
6: \(=-25\cdot75+25\cdot45-75\cdot45+75\cdot25\)
\(=45\left(25-75\right)=45\cdot\left(-50\right)=-2250\)
7: \(=-54\cdot\left(-9\right)+35\cdot\left(-20\right)\)
\(=486-700=-214\)
8: \(=187-23-20+180=164+160=324\)
9: \(=512\left(2-128+128\right)=512\cdot2=1024\)
tính nhanh
a) -5/12+4/37+17/12-41/37
b) 1/2+-3/5:(-1/1/2)-|-2/5|
c)8^15 x 3^16/4^22 x 9^8
d)35/1/6:(-4/5)-45/1/6:(-4/5)
e) (5/12:10/3)+(1/2)^2
a, \(\frac{-5}{12}+\frac{4}{37}+\frac{17}{12}-\frac{41}{37}\)
\(=\left(-\frac{5}{12}+\frac{17}{12}\right)+\left[\frac{4}{37}+\left(-\frac{41}{37}\right)\right]\)
\(=1+\left(-1\right)\)
\(=-1\)
b, \(\frac{1}{2}+\left(-\frac{3}{5}\right):\left(-1\frac{1}{2}\right)-\left|-\frac{2}{5}\right|\)
\(=\frac{1}{2}+\left(-\frac{3}{5}\right):\left(-\frac{3}{2}\right)-\frac{2}{5}\)
\(=\frac{1}{2}+\frac{2}{5}-\frac{2}{5}\)
\(=\frac{1}{2}\)
Mấy bài còn lại tương tự bn tự làm nha tính số mũ ra xong thực hiện, lấy thừa số chung mà nhân ( H mik bận đi hc thêm rồi)