22 x 2
44 x 2
Tính nhanh
A= ( 38 x 333 - 111 x 133 ) x 2018
B = ( 25 + 3 x 75 - 125 x 2 ) : 20182019
C = ( 244 x 395 - 244 x 195 ) : ( 122 x 200 )
D = ( 355 x 45 x 55 ) : ( 11 x 9 x 7)
E = 1 x 2 + 2 x 3 + 3 x 4 + 4 x 5 + ... + 49 x 50
a: \(A=\left[111\cdot\left(38\cdot3-133\right)\right]\cdot2018\)
\(=111\cdot\left(-19\right)\cdot2018=-4255962\)
b: \(B=\left[25\left(1+3\cdot3-5\cdot2\right)\right]:20182019\)
\(=25\left(1+9-10\right):20182019=0\)
c: \(C=\dfrac{\left[244\left(395-195\right)\right]}{122\cdot200}=\dfrac{244}{122}=2\)
d: \(D=\dfrac{355\cdot45\cdot55}{11\cdot9\cdot7}=\dfrac{355\cdot5\cdot5}{7}=\dfrac{8875}{7}\)
244 x 395 - 151/244 + 395 x 243
\(\frac{244\times395-151}{244+395\times243}\)
\(=\frac{243\times395+395-151}{243\times395+244}\)
\(=\frac{243\times395+244}{243\times395+244}\)
\(=1\)
[ ( x + 54 ) - 32 ] x 2 = 244
[ ( x + 54 ) - 32 ] x 2 = 244
( x + 54 ) - 32 = 244 : 2 =122
x + 54 = 122 + 32 =154
x = 154 - 54 =100
=> (x+54)-32=244:2
=> (x+54)-32=122
=> x+54=122+32
=>x+54=154
=> x=154-54=100
t i c k cho mình nha cãm ơn
[ ( x + 54 ) - 32 ] x 2 = 244
( x + 54 ) - 32 = 244 : 2 =122
x + 54 = 122 + 32 =154
x = 154 - 54
x =100
tìm x [ ( x2+54)-32]*2=244
[(x^2+54)-32]*2=244
(x^2+54)-32=244/2
(x^2+54)-32=122
x^2+54=122+32
x^2+54=154
x^2=154-54
x^2=100
=> x=10 hoặc x=-10
[(x2+54)-32]*2=244
(x2+54)-32=244/2
(x2+54)-32=122
x2+54=122+32
x2+54=154
x2=154-54
x2=100=102
=>x=10
60 +2.(x+3) = 244
`60 + 2 . ( x + 3 ) = 244`
`2 . (x + 3 ) = 244 - 60`
`2. ( x + 3 ) = 184`
`x + 3 = 184 : 2`
`x + 3 = 92`
`x = 92 - 3`
`x = 89`
\(60+2\cdot\left(x+3\right)=244\\ 2\cdot\left(x+3\right)=244-60\\ 2\cdot\left(x+3\right)=184\\ x+3=184:2\\ x+3=92\\ x=92-3\\ x=89.\)
\(60+2\cdot(x+3)=244\\\Rightarrow 2 \cdot(x+3)=244-60\\\Rightarrow 2\cdot(x+3)=184\\\Rightarrow x+3=184:2\\\Rightarrow x+3=92\\\Rightarrow x=92-3\\\Rightarrow x=89\)
Vậy \(x=89\)
#\(Toru\)
[ (x2 + 54) - 32]. 2= 244
tìm x
[ 2. ( 70 - x ) + 72 ]: 2 =46
[ ( 2.x + 54 ) - 32 ] . 2 = 244
[ 2. ( 70 - x ) + 72 ]: 2 =46
2. ( 70 - x ) + 72 = 46.2
2. ( 70 - x ) + 72 = 92
2. ( 70 - x ) =92-72
2. ( 70 - x ) =20
70-x=20:2
70-x=10
x=70-10
x=60
[ ( 2.x + 54 ) - 32 ] . 2 = 244
( 2.x + 54 ) - 32 = 244:2
( 2.x + 54 ) - 32 = 122
2.x + 54 = 122+32
2.x + 54 = 154
2.x =154-54
2x=100
x=100:2
x=50
Tính giá trị của 240 x 246 - 244 x 244 bằng cách dùng hàng đẳng thức
\(=243^2-3^2-244^2=-496\)
[ ( x^2+54)-32]*2=244
Tính nhanh (244 X 395 - 151) / (244 + 395 X 243) . So sánh phân số với 1
224x395-151=223x395+395-151=223x395+224
nên: (244x395-151)/(224+395x243)=1