Ta thấy: 5^31 > 5^30 ; 9^19 < 9^20

Ta có: 5^30 = (5^3)^10 = 125^10

            9^20 = (9^2)^10 = 81^10

Mà: 125^10 > 81^10

Vậy: 5^31 > 9^19

Cảm ơn bạn HTN247 nhoa ~ :3

`2^(x+2) = 2^7`

`x = 5`

`x^3 = 46 + 18`

`x^3 = 64`

`x = 4`

`3(2x+1)^3 = 375`

`(2x+1)^3 = 125`

`2x + 1 = 5`

`x = 2`

`2^x .4 = 8^2 . 2`

`2^x . 4 =64.2`

`2^x .4 = 128`

`2^x = 128:4`

`2^x = 32`

`2^x=2^5`

`=> x=5`

___________________________

`x^3 - 6^2 : 2  = 46`

`x^3 - 18=46`

`x^3=46+18`

`x^3 = 64`

`x^3 = 4^3`

`=>x=4`

____________________

`25^2 - 3.(2x+1)^3 = 250`

`625 - 3.(2x+1)^3 = 250`

` 3.(2x+1)^3 =625-250`

`3.(2x+1)^3 =375`

`(2x+1)^3=375 : 3`

`(2x+1)^3 = 125`

`(2x+1)^3=5^3`

`2x+1=5`

`2x=5-1`

`2x=4`

`=>x=2`

`121-7.(x-1)=10`

`7.(x-1)=121-10`

`7.(x-1)=111`

`x-1=111:7`

`x-1=111/7`

`x=111/7 + 7/7`

`x=118/7`

Vậy `x=118/7`

\(121-7.\left(x-1\right)=10\)

\(7.\left(x-1\right)=121-10\)

\(7.\left(x-1\right)=111\)

\(x-1=111:7\)

\(x-1=\dfrac{111}{7}\)

\(x=\dfrac{111}{7}+1\)

\(x=\dfrac{187}{7}\)

3x^6-1=2

(=) 3x^6=2+1

(=) 3x^6=3

(=) x^6=3:3

(=)x^6=1

=> x=1

1. 324 + [ 112 - ( 112 + 324 ) ]

= 324 + ( 112 - 436)

= 324 + ( - 324 )

= 0

2. ( - 59 + 71 ) - ( - 83 - 59 )

= 12 - ( - 412 )

= 424

3. - 257 - [ ( - 257 + 156 ) - 56 ]

= - 257 - ( - 101 - 56 )

= - 257 - ( - 157 )

= - 100

`324 + [ 112 - ( 112 + 324 ) ]`

`= 324 + ( 112 - 436)`

`= 324 + ( - 324 )`

`=324-324`

`=0`

________________________________

` - 257 - [ ( - 257 + 156 ) - 56 ]`

`= - 257 - ( - 101 - 56 )`

`= - 257 - ( - 157 )`

`-257 + 157`

`= - 100`

_________________________
`-329 + (15-101)-(25-440)`

`=-329 + 15 - 101 - 25 + 440`

`=(-329 - 101) + (15-25)+440`

`=-430 + (-10)+440`

`=-430 - 10+440`

`=-440 +440`

`=0`

_____________________________________

`4524-(864 - 999) - (36 + 999)`

`=4524 - 864 + 999 - 36 - 999`

`=(4524 - 864 )+(999-999)-36`

`=3660 + 9 -36`

`=3624`

(62  +72 +82+92+102) - (12  +22 +32+42+52)=

(62 -12  ) +(72  - 22 )+( 82 - 32 )+( 92 - 42 )+(102  - 52 )=

(6 -1) x(6+1)+(7 - 2 )(7+2)+( 8 - 3 )(8+3)+( 9 - 4)(9+4)+(10  - 5 )(10+5)

= 5 (7+9+11+13+15)=5x55=275

=36+49+64+81+100-1-4-9-16-25

=275