49÷[(16-3x)+32]=47
47.52+49-47
168:{46-[12+5.(32:16)^2]}
6^7:6^4-4^1.4^0
ai nhanh cho minh 1 lai nhe .............................
a)11/53+(32/47+-10/53)+-64/94+1/53+1/3
b) (-1+45/115+47/51)+(-9/23+-1/3)
c) -13/49+12/48+1/12+3/18
d) 13/15+(-4/5+7/18)+-5/12+1/16
Tính nhanh
a)47/53x(17/3-53/47)+17/3x(6/17-47/53)
b)15/37x(38/41-75/45)-38/41x(15/37-82/76)
c)-41/32x(15/8-16/41)+15/8x(41/32-8/3)
Tính hợp lý:
45-58+(-45)+(+58)-3
(-57)-(-12)+3-(-57)
-(-24)-(-30)+(-24)-30+8
-(-12)+(+19)-(+12)+8-19
47-(-53)+(-47)-(+53)
-(+28)+32-(-28)+(-34)
15-(+72)+(-15)+(+72)
20-(+46)+(-25)-(-46)
28-(-32)+(-28)-32+5
-75+(-49)+(+75)+49-12
Giúp e vs ạ
45-58+(-45)+(+58)-3=45-58-45+58-3=(45-45)+(58-58)-3=-3
(-57)-(-12)+3-(-57)=-57+12+3+57=(-57+57)+12+3=15
-(-24)-(-30)+(-24)-30+8=24+30-24-30+8=(24-24)+(30-30)+8=8
-(-12)+(+19)-(+12)+8-19=12+19-12+8-19=(12-12)+(19-19)+8=8
47-(-53)+(-47)-(+53)=47+53-47-53=(47-47)+(53-53)=0
-(+28)+32-(-28)+(-34)=-28+32+28-34=(-28+28)-(34-32)=-2
15-(+72)+(-15)+(+72)=15-72-15+72=(15-15)+(72-72)=0
20-(+46)+(-25)-(-46)=20-46-25+46=(20-25)+(46-46)=-5
28-(-32)+(-28)-32+5=28+32-28-32+5=(28-28)+(32-32)+5=5
-75+(-49)+(+75)+49-12=-75-49+75+49-12=(-75+75)+(49-49)-12=-12
\(...=45-58-45+58-3=-3\)
\(...=-57+12+3+57=15\)
\(...=24+30-24-30+8=8\)
\(...=12+19-12+8-19=8\)
\(...=47+53-47-53=0\)
\(...=-28+32+28-34=-2\)
\(...=15-72-15+72=0\)
\(...=20-46-25+46=-5\)
\(=...28+32-28-32+5=5\)
\(...=-75-49+75+49-12=-12\)
So sánh các phân số bằng cách chọn phân số chung gian:
a, \(\dfrac{11}{32}\) và \(\dfrac{16}{49}\)
b, \(\dfrac{46}{71}\) và \(\dfrac{38}{55}\)
c, \(\dfrac{12}{47}\) và \(\dfrac{29}{117}\)
d, \(\dfrac{18}{53}\) và \(\dfrac{34}{103}\)
Giải chi tiết ra giúp mình nhé @ _ @
a: \(\frac{11}{32}>\frac{11}{33}=\frac13\)
\(\frac13=\frac{16}{48}>\frac{16}{49}\)
Do đó: \(\frac{11}{32}>\frac{16}{49}\)
b: \(\frac{46}{71}<\frac{46}{69}=\frac23\)
\(\frac23=\frac{38}{57}<\frac{38}{55}\)
Do đó: \(\frac{46}{71}<\frac{38}{55}\)
c: \(\frac{12}{47}>\frac{12}{48}=\frac14\)
\(\frac14=\frac{29}{116}>\frac{29}{117}\)
Do đó: \(\frac{12}{47}>\frac{29}{117}\)
d: \(\frac{18}{53}>\frac{18}{54}=\frac13\)
\(\frac13=\frac{34}{102}>\frac{34}{103}\)
Do đó: \(\frac{18}{53}>\frac{34}{103}\)
Thực hiện phép tính :
a) 123 - 27 + 27 + 13 - 123
b) 175 + 25 + 13 + 15 - 175 - 25
c) 53 x 39 + 47 x 39 + 53 x 21 + 47 x 21
d) 49 x 35 + 49 x 16 - 49 x 61
a) `123 - 27 + 27 + 13 - 123`
`= (123 - 123) + (27 - 27) + 13`
`= 0 + 0 + 13`
`= 13`
`---`
b) `175 + 25 + 13 + 15 - 175 - 25`
`= (175-175)+(25-25)+25+13`
`=0+0+25+13`
`=28`
`---`
c) \(53\times39+47\times39+53\times21+47\times21\)
\(=\text{[}\left(53+47\right)\times39]+\left[\left(53+47\right)\times21\right]\)
\(=\left(100\times39\right)+\left(100\times21\right)\)
\(=3900+2100\)
`=6000`
`---`
d) \(49\times35+49\times16-49\times61\)
`=` \(49\times\left(35+16-61\right)\)
`=` \(49\times\left(-10\right)\)
`=-490`
Giải phương trình
a,\(\frac{x+16}{49}+\frac{x+18}{47}=\frac{x+20}{45}-1\)
b,\(\frac{x-69}{30}+\frac{x-67}{32}+\frac{x-65}{34}=\frac{x-63}{36}+\frac{x-61}{38}+\frac{x-59}{40}\)
c,(2x-5)3-(3x-4)3+(x+1)3=0
d,(x2+3x-4)3+(3x2+7x+4)3=(4x2+10x)3
\(\left(8x^3-60x^2+150x-125\right)-\left(27x^3-108x^2+144x-64\right)+\left(x^3+3x^2+3x+1\right)=0\)
\(-18x^3+51x^2+9x-60=0\)
\(\left(2x-5\right)\left(x+1\right)\left(3x-4\right)=0\)
\(\left[\begin{array}{nghiempt}x=\frac{5}{2}\\x=-1\\x=\frac{4}{3}\end{array}\right.\)
(25-32)-(7+x)=47-25
3x-16=40+x
2(4x-30)-3(2x+15)=-75
-4xI2x-3I=(-16):I-4I
Giúp mình càng sớm càng tốt nhoa!!!
Cảm ơn!!
(25-32)-(7+x)=47-25
-7 - ( 7 + x ) = 22
-7 - 7 - x = 22
- 14 - x = 22
x = 22 + ( - 14 )
x = 8
3x - 16 = 40 + x
3x - x = 40 + 16
2x = 56
x = 56 : 2
x = 28
-4 . | 2x - 3 | = ( - 16 ) : | - 4 |
-4 . | 2x - 3 | = ( - 16 ) : 4
-4 . | 2x - 3 | = -4
| 2x -3 | = -4 : ( - 4 )
| 2x - 3 | = 1
=> \(\orbr{\begin{cases}2x-3=1\\2x=3=-1\end{cases}\Rightarrow\orbr{\begin{cases}2x=1+3=4\\2x=-1+3=2\end{cases}\Rightarrow}\orbr{\begin{cases}x=4:2=2\\x=2:2=1\end{cases}}}\)
Vậy x = 2 hoặc 1
x - { 55 - [49 + ( -28 - x ) ]} = 13 - { 47+[25-(32-x)]}
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=?
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=1275