Question

Thực hiện phép tính :

2021. 1001 - 2021

135. 3³ + 5. ( 3³ . 4 - 3⁴ )

Answer 1

2021.1001 - 2021

= 2021.1001 - 2021. 1

= 2021. ( 1001 - 1 )

= 2021. 1000

= 2021000.

Answer 2

a: \(=2021\cdot\left(1001-1\right)=2021000\)

b: \(=135\cdot3^3+5\cdot3^3\cdot4-5\cdot3^4\)

\(=3^3\left(135+20\right)-5\cdot3^4\)

\(=3^3\cdot155-5\cdot3^4\)

\(=3^3\left(155-5\cdot3\right)=27\cdot140=3780\)