\(213=\)\(2.10^2\)   \(+1.10+3.10^0\)

\(421=4.10^2+2.10+1.10^0\) 

\(1256=1.10^3+2.10^2+1.10^0\) 

\(2006=2.10^3+0.10^2+0.10+6.10^0\) 

abc = a . 10 ^2 + b .10 + c .10 ^ 0

abcde = a.10 ^ 4 + b.10^3 + c.10^ 2+ d .10 + e . 10 ^ 0

k cho mk nha

213 = 2.10² + 1.10¹ + 3.10⁰

421 = 4.10² + 2.10¹ + 1.10⁰

2009 = 2.10³ + 0.10² + 0.10¹ + 9.10⁰

abc = a.10² + b.10¹ + c.10⁰

abcde = a.10⁴ + b.10³ + c.10² + d.10¹ + e.10⁰

\(213=2×10^2+1×10^1+3×10^0\)

\(421=4×10^2+2×10^1+1×10^0\)

\(2009=2×10^3+0×10^2+0×10^1+9×10^0\)

a﴿ 213 = 200 + 10 + 3 = 2.100 + 10 + 3 = 2.10^ 2 + 10^ 1 + 3

b﴿ 421 = 400 + 20 + 1 = 4.100 + 2.10 + 1 = 4.10^ 2+ 2.10^ 1 + 1

c﴿ 2009 = 2000 + 9 = 2 . 1000 + 9 = 2.10 ^3 + 9

d﴿ abc = a.100 + b.10 + c = a.10^ 2 + b.10^ 1 + c

e﴿ abcde = a.10000 + b.1000 + c.100 + d.10 + e = a.10^ 4+ b.10^ 3+ c.10 ^2+ d.10^ 1 + e

a﴿ 213 = 200 + 10 + 3 = 2.100 + 10 + 3 = 2.10 2 + 10 1 + 3

b﴿ 421 = 400 + 20 + 1 = 4.100 + 2.10 + 1 = 4.10 2+ 2.10 1 + 1

c﴿ 2009 = 2000 + 9 = 2 . 1000 + 9 = 2.10 3 + 9

d﴿ abc = a.100 + b.10 + c = a.10 2 + b.10 1 + c

e﴿ abcde = a.10000 + b.1000 + c.100 + d.10 + e = a.10 4+ b.10 3+ c.10 2+ d.10 1 + e

213= 10 mũ 2+10 mũ 2+10 mũ 1 cộng 10 mũ 0 cộng 10 mũ 0 cộng 10 mũ 0

421=10 mũ 2+10  mũ 2+10 mũ 2+10 mũ 2 +10 mũ 1 + 10 mũ 1 +10 mũ 0

2009=10 mũ 3 + 10 mũ 3 + 10 mũ 0+10 mũ 0  + 10 mũ 0 +10 mũ 0 +10 mũ 0 +10 mũ 0 +10 mũ 0  +10 mũ 0+10 mũ 0 +10 mũ 0

abc= a.10 mũ 2+b.10 +c.10 mũ 0

abcde = 10 mũ 4.a +10 mũ 3.b +10 mũ 2.c +10.d +10 mũ 0.e

\(213=10^2+10^2+10^1+10^0+10^0+10^0\)

\(421=10^2+10^2+10^2+10^2+10^1+10^1+10^0\)

\(2009=10^3+10^3+10^0+10^0+10^0+10^0+10^0+10^0+10^0+10^0+10^0\)

\(abc=10^2\times a+10^1\times b+10^0\times c\)

\(abcde=10^4\times a+10^3\times b+10^2\times c+10^1\times d+10^0\times e\)

\(213=200+10+3=2\cdot100+10+3=2\cdot10^2+10^1+3\)

\(421=400+20+1=4\cdot100+2\cdot10+1=4\cdot10^2+2\cdot10^1+1\)

\(2009=2000+9=2\cdot1000+9=2\cdot10^3+9\)

\(abc=a\cdot100+b\cdot10+c=a\cdot10^2+b\cdot10^1+c\)

\(abcde=a\cdot10000+b\cdot1000+c\cdot100+d\cdot10+e=a\cdot10^4+b\cdot10^3+c\cdot10^2+d\cdot10^1+e\)

a﴿ 213 = 200 + 10 + 3 = 2.100 + 10 + 3 = 2.10 ² + 10 ¹ + 3

b﴿ 421 = 400 + 20 + 1 = 4.100 + 2.10 + 1 = 4.10 ²+ 2.10 ¹ + 1

c﴿ 2009 = 2000 + 9 = 2 . 1000 + 9 = 2.10 ³ + 9

d﴿ abc = a.100 + b.10 + c = a.10 ² + b.10 ¹ + c

e﴿ abcde = a.10000 + b.1000 + c.100 + d.10 + e = a.10 ⁴+ b.10 ³+ c.10 ²+ d.10 ¹ + e

213=10²+10²+10¹+10⁰

421=4*10²+2*10¹+10⁰

2009=2*10³+9*10⁰

abc=a*10²+b*10¹+c*10⁰

abcde=a*10⁴+b*10³+c*10²+d*10¹+e*10⁰

\(2\cdot2\cdot2\cdot3\cdot3=2^3\cdot3^2\)

a) 213 = 2.10^2 + 1.10 + 3.10^0

b) 421 = 4.10^2 + 2.10 + 1.10^0

c) 1256 = 1.10^3 + 2.10^2 + 5.10 + 6.10^0

d) 2006 = 2.10^3 + 0.10^2 + 0.10 + 6.10^0

e) abc = a.10^2 + b.10 + c. 10^0

g) abcde = a.10^4 + b.10^3 + c.10^2 + d.10 + e.10^0

a) 213= 2.100+1.10+3=2.10²+1.10+3.10⁰      b) 421=4.100+2.10+1=4.10²+2.10+1.10⁰

c)1256=1.1000+2.100+5.10+6=1.10³⁺2.10²+5.10+6.10⁰   d) 2006=2.1000+0.100+0.10+6=2.10³+0.10²+0.10+6.10⁰

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