1+2-3-4+.....+97+98-99-100=

=1+(2-3-4)+5+.....+97+(98-99-100)

=1+0+0+0+......+0+(-101)

=1+(-101)

=-100

k nha đúng

pls

(5x-1)^3=-1/8

5x-1 = -1/2

5x= -1/2+1

5x = 1/2

x=1/2.1/5

x=1/10

Vậy x=1/10

(5x-1)³ = (-1/2)³

<=>5x-1=-1/2

<=>x=1/10

\(\left(\frac{2}{3}-x\right)^2=\frac{1}{4}\)

\(\left(\frac{2}{3}-x\right)^2=\left(\frac{1}{2}\right)^2\)

\(\Rightarrow\frac{2}{3}-x=\frac{1}{2}\)

\(x=\frac{2}{3}-\frac{1}{2}\)

\(x=\frac{1}{6}\)

\(\left(\frac{2}{3}-x\right)^2=\frac{1}{4}\)

\(\left(\frac{2}{3}-x\right)^2=\left(\pm\frac{1}{2}\right)\)

\(\Rightarrow\hept{\begin{cases}\frac{2}{3}-x=\frac{1}{2}\\\frac{2}{3}-x=-\frac{1}{2}\end{cases}\Rightarrow\hept{\begin{cases}x=\frac{1}{6}\\x=\frac{7}{6}\end{cases}}}\)

Vậy \(x\left\{\frac{1}{6};\frac{7}{6}\right\}\)

X=1,5

k nhé

mình hứa sẽ k lại

Trả lời:

c, (8x-12)^4=0

   (8x-12)^4=0^4

   8x-12=0

   8x=12

  x=12:8

  x=1,5

 Học tốt

\(x.\left(\frac{-5}{4}\right)^7=\left(\frac{-5}{4}\right)^8\)

\(\Rightarrow x=\left(\frac{-5}{4}\right)^8:\left(\frac{-5}{4}\right)^7=\frac{-5}{4}\)

( - 4,7 ) + x = ( -1,8 ) 

=> x = ( - 1,8 ) - ( - 4,7 )

=> x = 2,9

HT

Tìm x biết

( - 4,7 ) + x = ( - 1,8 )

                x = ( - 1,8 ) - ( - 4,7 )

                x = ( - 1,8 ) + 4,7

                x = 2,9

Hok tốt

a) ( -7 )⁵ . ( -7 )⁶ = ( -7 )¹¹

b) ( -0,7 )¹⁰ : ( -0,7 )⁶ = ( -0,7 )⁴

\(\text{c)}\left(\frac{9}{5}\right)^3.\left(\frac{9}{5}\right)^{10}=\left(\frac{9}{5}\right)^{13}\)

\(\text{d) }\left(\frac{-1}{3}\right)^{30}.\left(\frac{1}{3}\right)^{15}=\left(\frac{1}{3}\right)^{30}.\left(\frac{1}{3}\right)^{15}=\left(\frac{1}{3}\right)^{45}\)

a) \(\left(-7\right)^5.\left(-7\right)^6\)\(=\left(-7\right)^{11}\)

b)\(\left(-0,7\right)^{10}:\left(-0,7\right)^6\)\(=\left(-0,7\right)^4\)

c) \(\left(\frac{9}{5}\right)^3.\left(\frac{9}{5}\right)^{10}=\left(\frac{9}{5}\right)^{13}\)

d) \(\left(-\frac{1}{3}\right)^{30}.\left(\frac{1}{3}\right)^{15}=\left(-\frac{1}{3}\right)^{45}\)

kẻ Nx song song với AB => góc BAN + ANx = 180^o (2 góc trong cùng phía)

=> góc xNE + NEF = 180^o do góc BAN + ANE + NEF = 360^o

mà 2 góc này ở vị trí cùng phía => Nx // EF => AB // EF (1)

kẻ My song song với AB => góc BAM = AMy (SLT)

mà BAM + MCD = AMC  = AMy + yMC 

=> MCD = yMC mà 2 góc này ở vị trí SLT => My // CD => AB // CD  (2)

Từ (1)(2) => CD // EF