cho S=4^0+4^1+4^2+...+4^35
so sánh 3S với 64^12
Cho S = 4^0 + 4^1 + 4^2 + 4^3 +...+ 4^35Hãy so sánh 3S với 64^12
\(4^0+4^1+4^2+4^3+...+4^{35}\\ 4S=4^1+4^2+4^3+4^4+...+4^{36}\\ 4S-S=\left(4^1+4^2+4^3+4^4+...+4^{36}\right)-\left(4^0+4^1+4^2+4^3+...+4^{35}\right)\\ 3S=4^{36}-1=64^{12}-1\\ Vì64^{12}-1< 64^{12}\\ \Rightarrow3S< 64^{12}\)
Ta có: \(64^{12}=\left(4^3\right)^{12}=4^{36}\)
\(S=4^0+4^1+...+4^{34}+4^{35}\)
\(\Rightarrow4S=4^1+4^2+...+4^{35}+4^{36}\)
\(\Rightarrow4S-S=4^{36}-4^0\)
\(\Rightarrow3S=4^{36}-1< 4^{36}\)
Vậy \(3S< 64^{12}\)
Cho S= 40+41+4243+...+435
Hãy so sánh 3S với 6412
4S=4.(40+41+43+...+435)
4S=41+42+...+436
4S-S=(41-41)+(42-42)+...+(335-335)+336-30
3S=0+0+...+0+336-1
6412=(34)12=336
vỉ 336-1<336 nên 3S<6412
Cho S = 4^0+4^1+4^2+4^3+4^4+....+4^35
Hãy so sánh 3S với 64^12
*Chú thích: 4^1= bốn mũ một(tại điện thoại ko có dấu mũ )
\(S=4^0+4^1+4^2+4^3+...+4^{35}\)
\(4S=4^1+4^2+4^3+...+4^{36}\)
\(4S-S=(4^1+4^2+4^3+...+4^{36})-(4^0+4^1+4^2+4^3+...+4^{35})\)
\(3S=4^{36}-4^0\)
\(S=4^{36}-1\)
\(\text{Ta thấy :}64^{12}=(4^3)^{12}=4^{36}\)
\(\text{Mà }4^{36}-1>4^{36}\text{ nên }3S>A\)
Cho S = 4^0 + 4^1 + 4^2 + 4^3 + ... + 4^35
Hãy so sánh 3S với 64^12
\(S=1+4+4^2+.....+4^{35}\)
\(\Leftrightarrow4S=4+4^2+4^3+........+4^{36}\)
\(\Leftrightarrow4S-S=\left(4+4^2+......+4^{36}\right)-\left(1+4+4^2+......+4^{35}\right)\)
\(\Leftrightarrow3S=4^{36}-1\)
\(\Leftrightarrow3S+1=4^{36}=\left(4^3\right)^9=64^9< 64^{12}\)
\(\Leftrightarrow3S+1< 64^{12}\)
Cho S= 40+41+42+43+44+.....+434+435 . So sánh 3S và 6412
Ta có
S=40+41+42+...+434+435
=>4S=41+42+43+...+435+436
=> 4S-S=(40+41+42+...+434+435)- (41+42+43+...+435+436)
=> 3S=436-40=436-1=6412-1
=> 3S<6412
Cho S = 40 + 41 + 42 + 43 + ............ +435
So sánh 3S và 6412
Dễ thấy:64^{12}=\left(4^3\right)^{12}=4^{3.12}=4^{36}6412=(43)12=43.12=436
Ta có: 4S=4\left(4^0+4^1+4^2+4^3+...+4^{35}\right)4(40+41+42+43+...+435)
=4^1+4^2+4^3+4^4+...+4^{36}=41+42+43+44+...+436
=>4S-S=4^{36}-4^0436−40
Hay 3S=4^{36}-1< 4^{36}=64^{12}436−1<436=6412
Vậy 3S<64^{12}6412
Cho S= 40 + 41 + 42 + 43 +....+ 435
So sánh 3S với 6412
\(S = 1 + 4 + 4^ 2 + ... + 4\)35
\(4S = 4 + 4^2 + 4 ^ 3 + ... + 4\)36
\(4S - S = ( 1 + 4 + 4^ 2 + ... + \)436\()\) \(- ( 1 + 4 + 4 ^ 2 + ... + 4\)35 \()\)
\(3S = 4\)36 \(- 1\)
\(3S = 64\)12 - 11
\(Ta thấy : 64\)12 \(- 1 < 64\)12
\(Do đó : 3S < 64\)12
\(Vậy : 3S < 64\)12
Cho S = 40 + 41 + 42 + 43 + ........... + 435
So sánh : 3S và 6412
S = 40 + 41 + 42 + 43 + ........... + 435
=> 4S = 4.( 40 + 41 + 42 + 43 + ........... + 435 )
=> 4S = 41+42 + 43 + ... + 436
=> 3S = ( 41+42 + 43 + ... + 436 ) - ( 40 + 41 + 42 + 43 + ........... + 435 )
=> 3S = 436 - 40 = 436 - 1
Ta có : 436 - 1 = ( 43 )12 - 1 = 6412 - 1 < 6412
Vậy 3S < 6412
Bạn nhân 4S = 4( 40+41+......+435) = 41+42+43+......+436
Lấy 4S - S = 3S = 41+42+43+......+436- (40+41+42......+435) = 436- 1
3S = 436- 1 = (43)12-1 = 6412-1 < 6412
Cho S= 40+41+42+43+...+ 435
Hãy so sánh 3S với 6412
Ta có: \(S=4^0+4^1+...+4^{35}\)
\(\Rightarrow4S=4+4^1+...+4^{36}\)
\(\Rightarrow4S-S=\left(4+4^1+...+4^{36}\right)-\left(4^0+4^1+...+4^{35}\right)\)
\(\Rightarrow3S=4^{36}-4^0\)
\(\Rightarrow3S=\left(4^3\right)^{12}-1\)
\(\Rightarrow3S=64^{12}-1\)
Vì \(64^{12}-1< 64^{12}\) nên \(3S< 64^{12}\)
Vậy \(3S< 64^{12}\)
Ta có: S=40+41+...+435S=40+41+...+435
⇒4S=4+41+...+436⇒4S=4+41+...+436
⇒4S−S=(4+41+...+436)−(40+41+...+435)⇒4S−S=(4+41+...+436)−(40+41+...+435)
⇒3S=436−40⇒3S=436−40
⇒3S=(43)12−1⇒3S=(43)12−1
⇒3S=6412−1⇒3S=6412−1
Vì 6412−1<64126412−1<6412 nên 3S<64123S<6412
Vậy 3S<6412
v
Ta có: S=40+41+...+435S=40+41+...+435
⇒4S=4+41+...+436⇒4S=4+41+...+436
⇒4S−S=(4+41+...+436)−(40+41+...+435)⇒4S−S=(4+41+...+436)−(40+41+...+435)
⇒3S=436−40⇒3S=436−40
⇒3S=(43)12−1⇒3S=(43)12−1
⇒3S=6412−1⇒3S=6412−1
Vì 6412−1<64126412−1<6412 nên 3S<64123S<6412
Vậy 3S<6412