a) \(2^x\)\(-\)\(64\)\(=\)\(2^6\)
\(2^x\)\(-\)\(2^6\)\(=\)\(2^6\)
\(2^x\) \(=\)\(2^6\)\(+\)\(2^6\)
\(2^x\) \(=\) \(64\)\(+\)\(64\)
\(2^x\) \(=\) \(128\)
\(\Rightarrow\) \(2^x\) \(=\) \(2^7\)
b) \(\left(7x-11\right)\)\(^3\)\(=\)\(2^5\)\(.\)\(5^2\)\(+\)\(200\)
\(\left(7x-11\right)\)\(^3\)\(=\)\(32\)\(.\)\(25\)\(+\)\(200\)
\(\left(7x-11\right)\)\(^3\)\(=\) \(1000\)
\(\left(7x-11\right)\)\(^3\)\(=\) \(10^3\)
\(\Rightarrow\)\(7x-11\)\(=\)\(10\)
\(7x\) \(=\)\(10+11\)
\(7x\) \(=\) \(21\)
\(x\) \(=\) \(21\)\(:\)\(7\)
\(x\) \(=\) \(3\)
\(2^x-64=2^6\)
\(2^x-64=64\)
\(2^x=64+64\)
\(2^x=128\)
\(\)Vì \(128=2^7\) \(\Rightarrow x=7\)
a, 2x-64=26
=> 2x-64=64
=> 2x=64-64
=> 2x=0
=> x=0
b, (7x-11)3=25.52+200
=> (7x-11)3=32.25+200
=> (7x-11)3=1000
=> (7x-11)3=103
=> 7x-11=10
=> 7x=10+11
=> 7x=21
=> x=21:7
=> x=3
a) \(2^x-64=2^6\)
\(2^x=2^6+64\)
\(2^x=64+64\)
\(2^x=128\)
\(2^x=2^7\)
\(\Rightarrow x=7\)
vay \(x=7\)
b) \(\left(7x-11\right)^3=2^5.5^2+200\)
\(\left(7x-11\right)^3=800+200\)
\(\left(7x-11\right)^3=1000\)
\(\left(7x-11\right)^3=10^3\)
\(\Rightarrow7x-11=10\)
\(\Rightarrow7x=21\)
\(\Rightarrow x=3\)
vay \(x=3\)
\(a,2^x-64=2^6\)
\(2^x-64=64\)
\(2^x=64+64\)
\(2^x=128\)
\(2^x=2^7\Rightarrow x=7\)
\(b,\left(7x-11\right)^3=2^5.5^2+200\)
\(\left(7x-11\right)^3=32.25+200\)
\(\left(7x-11\right)^3=1000\)
\(\left(7x-11\right)^3=10^3\)
\(\Rightarrow7x-11=10\)
\(7x=10+11\)
\(7x=21\)
\(x=21\div7\)
\(x=3\)
Tìm x thuộc N
a, 2x-64=26
2x-64=64
2x=64+64
2x=128
2x=27
x=7
b, (7x-11)3=25.52+200
(7x-11)3= 32.25+200
(7x-11)3= 1000
(7x-11)3=103
7x-11=10
7x =10+11
7x= 21
x= 21:7
x=3
HOK TỐT nhé
Bài làm:
a) \(2^x-64=2^6\)
\(\Leftrightarrow2^x=128\)
\(\Leftrightarrow2^x=2^7\)
\(\Rightarrow x=7\)
b) \(\left(7x-11\right)^3=800+200\)
\(\Leftrightarrow\left(7x-11\right)^3=1000\)
\(\Leftrightarrow\left(7x-11\right)^3=10^3\)
\(\Rightarrow7x-11=10\)
\(\Leftrightarrow7x=21\)
\(\Rightarrow x=3\)
