Rút gọn (3 + 1) (3^2 + 1) (3^4 + 1) … (3^64 + 1)
rút gọn p/s sau:
(3/4 - 3/16 - 3/64 - 3/256) / (1 - 1/4 - 1/16 - 1/64)
\(\text{A = (3 + 1) (3^2+ 1) (3^4 + 1) ... (3^{64} + 1)}\)Rút gọn biểu thức:
\(A=\left(3+1\right)\left(3^2+1\right)\left(3^4+1\right)...\left(3^{64}+1\right)\)
Ta có \(A=\left(3+1\right)\left(3^2+1\right)\left(3^4+1\right)\cdot\cdot\cdot\left(3^{64}+1\right)\)
\(\Rightarrow2A=\left(3-1\right)\left(3+1\right)\left(3^2+1\right)\left(3^4+1\right)\cdot\cdot\cdot\left(3^{64}+1\right)\)
\(=\left(3^2-1\right)\left(3^2+1\right)\left(3^4+1\right)\cdot\cdot\cdot\left(3^{64}+1\right)\)
\(=\left(3^4-1\right)\left(3^4+1\right)\cdot\cdot\cdot\left(3^{64}+1\right)\)
\(=\left(3^{64}-1\right)\left(3^{64}+1\right)=\left(3^{128}-1\right)\)
\(\Rightarrow A=\frac{3^{128}-1}{2}\)
Rút gọn biểu thức:
A = (3 + 1) (32 + 1) (34 + 1) ... (364 + 1)
Ta có : A = (3 + 1) (32 + 1) (34 + 1) ... (364 + 1)
=> 8A = (32 - 1)(32 + 1)(34 + 1)......(364 + 1)
=> 8A = (34 - 1)(34 + 1)......(364 + 1)
=> 8A = (364 - 1)(364 + 1)
=> A = \(\frac{3^{64}-1}{8}\)
Rút gọn biểu thức : a . A = 4 √25x/4 - 8/3 √9x/4 - 4/3x √9x³/64 ( với x ≥ 0 ) b. B = y/2 + 3/4 √1-4y+4y² - 3/2 ( với y ≤ 1/2 )
a: \(A=4\cdot\dfrac{5}{2}\sqrt{x}-\dfrac{8}{3}\cdot\dfrac{3}{2}\sqrt{x}-\dfrac{4}{3x}\cdot\dfrac{3x}{8}\cdot\sqrt{x}\)
\(=10\sqrt{x}-4\sqrt{x}-\dfrac{1}{2}\sqrt{x}\)
\(=\dfrac{11}{2}\sqrt{x}\)
b: \(B=\dfrac{y}{2}+\dfrac{3}{4}\cdot\left|2y-1\right|-\dfrac{3}{2}\)
\(=\dfrac{y}{2}+\dfrac{3}{4}\left(1-2y\right)-\dfrac{3}{2}\)
=1/2y+3/4-3/2y-3/2
=-y-3/4
Rút gọn biểu thức:
A = (3 + 1) (32 + 1) (34 + 1) ... (364 + 1)
A = (3 + 1) (32 + 1) (34 + 1) ... (364 + 1)
2A = (3 - 1)(3 + 1) (32 + 1) (34 + 1) ... (364 + 1)
2A = (32 - 1)(32 + 1) (34 + 1) ... (364 + 1)
= (34 - 1)(34 + 1) ... (364 + 1)
= (38 - 1)(38 + 1)(316+1)(332+1)(364+1)
= (316-1)(316+1)(332+1)(364+1)
= (332-1)(332+1)(364+1)
= (364-1)(364+1)
= (3128-1)
=> A = \(\frac{3^{128}-1}{2}\)
\(2A=2\left(3+1\right)\left(3^2+1\right)\left(3^4+1\right)...\left(3^{64}+1\right)\)
\(=\left(3-1\right)\left(3+1\right)\left(3^2+1\right)\left(3^4+1\right)...\left(3^{64}+1\right)\)
áp dụng hằng đẳng thức \(a^2-b^2\)
ta có 2A=\(3^{128}-1\)=>A=\(\frac{3^{128}-1}{2}\)
Rút gọn biểu thức sau A = 3(22+1)(24+1)...(264+1)+1
A = (22 - 1) (22 +1)(24 +1)...(264 +1) + 1 = (24 - 1)(24 +1)...(264 +1) + 1 = (28 -1)...(264 +1) + 1 = 2128 -1 + 1 = 2128
rút gọn biểu thức sau :
( 3 + 1 ) x ( 3^2 + 1 ) x ( 3^4 + 1 ) x ( 3^8 +1 ) x ( 3^16 +1 ) x ( 3^32 +1 ) x ( 3^64 +1 )
các bạn giúp mk vs nhé ! cảm ơn nhiều !!!
Đặt biểu thức đã cho là A.
Ta có: 2A = (3 - 1) * (3 + 1) * (3^2 + 1) * .... * (3^64 + 1)
= (3^2 - 1) * (3^2 + 1) * ... * (3^64 + 1) (hằng đẳng thức a^2 - b^ 2 = (a+b)(a-b))
Rút gọn triệt tiêu ta được 2A=3^64 - 1
=> A = (3^64 - 1)/2
Rút gọn biểu thức:
A = (3 + 1) (32 + 1) (34 + 1) ... (364 + 1)
\(A=\left(3+1\right)\left(3^2+1\right)...\left(3^{64}+1\right)\)
\(\Leftrightarrow\left(3-1\right)A=\left(3-1\right)\left(3+1\right)\left(3^2+1\right)...\left(3^{64}+1\right)\)
\(\Leftrightarrow2A=\left(3^2-1\right)\left(3^2+1\right)\left(3^4+1\right)...\left(3^{64}+1\right)\)
\(\Leftrightarrow2A=\left(3^4-1\right)\left(3^4+1\right)\left(3^8+1\right)...\left(3^{64}+1\right)\)
\(\Leftrightarrow2A=3^{128}-1\)
\(\Leftrightarrow A=\frac{3^{128}-1}{2}\)
Rút gọn biểu thức sau
B=3*(22+1)*(24+1)*...*(264+1)
B=3.(2^2+1)(2^4+1)...(2^64+1)
=(2^2-1)(2^2+1)(2^4+1)...(2^64+1)
=(2^4-1)(2^4+1)...(2^64+1)
=(2^8-1)...(2^64+1)
.......
=(2^64-1)(2^64+1)
=2^128-1