3+2x9
(-0.2)^2x5-(8^2x9^5)/3^9x4^3
\(=0.04\cdot5-\dfrac{2^6\cdot3^{10}}{3^9\cdot2^6}=0.2-3=-2.8\)
2181x729+243x81x27/3^2x9^2+18x54x162x9+723x729
(1+2+3+4+5+6+7+8+9)x(2x9-18)
(1+2+3+4+5+6+7+8+9)x(2x9-18)
=(1+2+3+4+5+6+7+8+9)x(18-18)
=(1+2+3+4+5+6+7+8+9)x0
=0
P/s: lần sau đăng đúng môn nha
1+3++6+10+15+..........+45+55
1x10+2x9+3x8+...........+8x3+9x2+10x1
2x9=
tim x
a,2/3:2/3xX=1
b, X+X:5x7,5+X:2x9=315
a) \(\frac{2}{3}:\frac{2}{3}\times x=1\)
\(1\times x=1\)
x = 1
b) \(x+x:5\times7,5+x:2\times9=315\)
\(x+x\cdot\frac{1}{5}\cdot7,5+x\cdot\frac{1}{2}\cdot9=315\)
\(x\cdot\left(1+\frac{1}{5}.7,5+\frac{1}{2}.9\right)=315\)
x.7 = 315
x = 45
Dấu . là dấu nhân nha
Tìm x :
a) 2/3 : 2/3 × X = 1
1 × X = 1
X = 1 : 1
X = 1
b) X + X : 5 × 7,5 + X : 2 × 9 = 315
X + X × 1/5 × 7,5 + X × 1/2 × 9 = 315
X × 1 + X × 1,5 + X × 4,5 = 315
X × ( 1 + 1,5 + 4,5 ) = 315
X × 7 = 315
X = 315 : 7
X = 45
VẬY X = 45
2x9=18
10+2x9=?
10 + 2 x 9 = 10 + 18
= 28
ai thấy mình làm đúng thì k nhé