Rút gọn: \(A=\frac{1+3^4+3^8+3^{12}}{1+3^2+3^4+3^6+3^8+3^{10}+3^{12}+3^{14}}\)
rút gọn
Q=\(\frac{1+3^4+3^8+3^{12}}{1+3^2+3^4+3^6+3^8+3^{10}+3^{12}+3^{14}}\)
Ta có
• A=1+34+38+312
=>34.A=34+38+312+316
<=>81.A-A=316-1
<=>A=(316-1)/80=538084
•B=1+32+34+36+38+310+312+314
=>32.B=32+34+36+38+310+312+314+316
<=>8.B=316-1
<=>B=(316-1)/8=53808400
Vậy Q=A/B=538084/53808400=1/100=0.01
Sửa lại:
B=5380840
=>Q=1/10
Rút gọn :
Q=\(\frac{1+3^4+3^8+3^{12}}{1+3^2+3^4+3^6+3^8+3^{10}+3^{12}+3^{14}}\)
\(Q=\frac{1+3^4+3^8+3^{12}}{\left(1+3^4+3^8+3^{12}\right)+3^2\left(1+3^4+3^8+3^{12}\right)}\)
\(Q=\frac{1+3^4+3^8+3^{12}}{10\left(1+3^4+3^8+3^{12}\right)}=\frac{1}{10}\)
Cj ko rep đc kịp sr nha
Rút gọn :C=1+3^4+3^8+3^12/1+3^2+3^4+3^6+3^8+3^10+3^12+3^14
Rút gọn
1+3^4+3^8+3^12/1+3^2+3^4+3^6+3^8+3^10+3^12+3^14
Rút gọn biểu thức
A=\(\frac{1+3^4+3^8+3^{12}}{1+3^2+3^4+3^6+3^8+3^{10}+3^{12}+3^{14}}\)
Giúp mình với ạ. Cảm ơn mọi người nhiều
Bài 1: tìm giá trị biểu thức:
\(\frac{12^4.\left(-10\right)^2}{3^4.4^5.5^2}\)
Bài 2: rút gọn:
\(A=\frac{1+3^4+3^8+3^{12}}{1+3^2+3^4+3^6+3^8+3^{10}+3^{12}+3^{14}}\)
Rút gọn các biểu thức sau :\(\frac{4^{10}+8^4}{4^5+8^6}\)
\(\frac{1+3^4+3^8+3^{12}}{1+3+3^4+3^6+3^8+3^{10}+3^{12}+3^{14}}\)
\(\frac{4^{10}+8^4}{4^5+8^6}=\frac{\left(2^2\right)^{10}+\left(2^3\right)^4}{\left(2^2\right)^5+\left(2^3\right)^6}=\frac{2^{2.10}+2^{3.4}}{2^{2.5}+2^{3.6}}=\)
\(=\frac{2^{20}+2^{12}}{2^{10}+2^{18}}\)
\(\frac{4^{10}+8^4}{4^5+8^6}=\frac{2^{20}+2^{12}}{2^{10}+2^{18}}=\frac{2^{12}.2^8+2^{12}}{2^{10}+2^{10}.2^8}=\frac{2^{12}\left(1+2^8\right)}{2^{10}\left(1+2^8\right)}=\frac{2^{12}}{2^{10}}=2^2=4\)
Rút gọn:
A = \(\frac{1+3^4+3^8+3^{12}}{1+3^2+3^4+3^6+..+3^{14}}\)
Áp dụng câu trên vào
\(A=\frac{B}{C}\Rightarrow B=\frac{3^{16}-1}{3^4-1};C=\frac{3^{16}-1}{3^2-1}\)
\(A=\frac{B}{C}=\frac{3^2-1}{3^4-1}=\frac{3^2-1}{\left(3^2-1\right)\left(3^2+1\right)}=\frac{1}{10}\)
Rút gọn
;
A=1+3^4+3^8+3^12/1+3^2+3^4+3^6+3^8+3^10+3^12