Bài 5: Lũy thừa của một số hữu tỉ

=>x+1/3=0 hoặc 2^x-16=0

=>x=-1/3 hoặc x=4

1) (1/2)² . (2/5)²

= (1/2 . 2/5)²

= (1/5)²

= 1/25

2) (5/4)² : (-35/24)²

= [5/4 : (-35/24)]²

= (-6/7)²

= 36/49

3) 25 . 5 - 1 . 50

= 125 - 50

= 75

\(\left(-\dfrac{5}{6}.x+\dfrac{5}{4}\right):\dfrac{3}{2}=\dfrac{4}{3}< =>-\dfrac{5}{6}.x+\dfrac{5}{4}=2< =>-\dfrac{5}{6}.x=\dfrac{3}{4}< =>x=-\dfrac{9}{10}\)

Vậy ....

a: =>11/12x=1/12+5/6=1/12+10/12=11/12

=>x=1

d: =>x-2/3=3/4-5/6=9/12-10/12=-1/12

=>x=-1/12+8/12=7/12

b: =>1/4x=1

=>x=4

e: =>-11/9x=-2/3-8/3=-10/3

=>x=10/3:11/9=10/3*9/11=90/33=30/11

f: =>3/2x=2-5/4=3/4

=>x=1/2

c: =>1/3:x=3/5-2/3=9/15-10/15=-1/15

=>x=-1/3:1/15=-5

\(=\dfrac{100}{123}:\dfrac{9+7}{12}+\dfrac{23}{123}:\dfrac{27-7}{15}\)

\(=\dfrac{100}{123}\cdot\dfrac{3}{4}+\dfrac{23}{123}\cdot\dfrac{3}{4}=\dfrac{3}{4}\cdot1=\dfrac{3}{4}\)

`5/23+7/17+0,25-5/23+10/17`

`=5/23+7/17+1/4-5/23+10/17`

`=(5/23-5/23)+(7/17+10/17)+1/4`

`= 0 + 1+1/4`

`= 1 +1/4`

`=4/4+1/4`

`=5/4`

\(\dfrac{5}{23}+\dfrac{7}{17}+0,25-\dfrac{5}{23}+\dfrac{10}{17}\\ =1+0,25=1,25\)

\(=\dfrac{5}{23}+\dfrac{7}{17}+\dfrac{1}{4}-\dfrac{5}{23}+\dfrac{10}{17}=\left(\dfrac{5}{23}-\dfrac{5}{23}\right)+\left(\dfrac{7}{17}+\dfrac{10}{17}\right)+\dfrac{1}{4}=1+\dfrac{1}{4}=\dfrac{5}{4}\)

`3^x + 3^(x+1)= 324`

`=>3^x + 3^x.3=324`

`=>3^x( 1+3)=324`

`=>3^x . 4=324`

`=>3^x=324:4`

`=>3^x=81`

`=>x=4`

=>3^x*4=324

=>3^x=81

=>x=4

=>3^x*4=324

=>3^x=81

=>x=4

d: \(=\dfrac{100}{123}:\dfrac{9+7}{12}+\dfrac{23}{123}:\dfrac{27-7}{15}\)

\(=\dfrac{100}{123}\cdot\dfrac{12}{16}+\dfrac{23}{123}\cdot\dfrac{15}{20}\)

\(=\dfrac{3}{4}\left(\dfrac{100}{123}+\dfrac{23}{123}\right)=\dfrac{3}{4}\)

c: \(=\dfrac{53}{4}\cdot\dfrac{-7}{4}-\dfrac{69}{4}\cdot\dfrac{-7}{4}\)

\(=\dfrac{-7}{4}\left(\dfrac{53}{4}-\dfrac{69}{4}\right)=\dfrac{-7}{4}\cdot\left(-4\right)=7\)

Còn câu a nha bạn

a: \(=\dfrac{-1}{8}\cdot4-2\cdot\dfrac{-1}{8}=\dfrac{-1}{8}\cdot2=\dfrac{-1}{4}\)

b: \(=\dfrac{5}{6}-\dfrac{9}{4}+\dfrac{7}{3}=\dfrac{11}{12}\)

c: \(=\left(\dfrac{3}{4}\right)^4-\dfrac{5}{8}=-\dfrac{79}{256}\)

d: \(=3-1+\dfrac{3}{2}=2+\dfrac{3}{2}=\dfrac{7}{2}\)

e: \(=3.25+3-13=6.25-13=-6.75\)

\(=\left(-125\cdot25\right)^5=\left(-5^3\cdot5^2\right)^5=-5^{25}\)