1.
a) \(3^3.9^{-1}\)
\(=27.\frac{1}{9}\)
\(=3.\)
b) \(25.5^{-1}.5^0\)
\(=25.\frac{1}{5}.1\)
\(=5.1\)
\(=5.\)
c) \(3^2.\frac{1}{243}.81^2.3^{-3}\)
\(=9.\frac{1}{243}.6561.\frac{1}{27}\)
\(=\frac{1}{27}.6561.\frac{1}{27}\)
\(=243.\frac{1}{27}\)
\(=9.\)
Chúc bạn học tốt!
a, \(3^3.9^{-1}\)
\(=27.\frac{1}{9}\)
\(=\frac{27}{9}=3\)
b, \(25.5^{-1}.5^0\)
\(=25.\frac{1}{5}.1\)
\(=\frac{25}{5}.1\)
\(=5.1\)
\(=5\)
c, \(3^2.\frac{1}{143}.81^2.3^{-3}\)
\(=9.\frac{1}{143}.6561.\frac{1}{3^3}\)
\(=9.\frac{1}{143}.6561.\frac{1}{27}\)
\(=9.\frac{1}{143}\left(6561.\frac{1}{27}\right)\)
\(=9.\frac{1}{143}.243\)
\(=\frac{9}{143}.243\)
\(=\frac{2187}{143}\)
Câu d tương tự các câu trên
a) \(3^3.9^{-1}=27.\frac{1}{9}=\frac{27}{9}=3\)
b) \(25.5^{-1}.5^0=25.\frac{1}{5}.1=5\)
c) \(3^2.\frac{1}{243}.81^2.3^{-2}=9.\frac{1}{243}.6561.\frac{1}{9}=\left(9.\frac{1}{9}\right)\left(\frac{1}{243}.6561\right)=1.27=27\)
d) \(3^2.2^5.\left(-\frac{3}{2}\right)^2=\left(9.\frac{4}{9}\right).2^5=4.32=128\)
a)
\(3^3\cdot9^{-1}\)
\(=3^3\cdot\left(3^2\right)^{-1}\)
\(=3^3\cdot3^{2\cdot\left(-1\right)}\)
\(=3^3\cdot3^{-2}=3^{3+\left(-2\right)}=3^{3-2}=3^1=3\)
b)
\(25\cdot5^{-1}\cdot5^0\)
\(=5^2\cdot5^{-1}\cdot5^0\)
\(=5^{2+\left(-1\right)+0}=5^{2-1+0}=5^1=5\)
c)
\(3^2\cdot\frac{1}{243}\cdot81^2\cdot3^{-3}\)
\(=3^2\cdot3^{-4}\cdot\left(3^4\right)^2\cdot3^{-3}\)
\(=3^2\cdot3^{-4}\cdot3^{4\cdot2}\cdot3^{-3}\)
\(=3^2\cdot3^{-4}\cdot3^8\cdot3^{-3}=3^{2+\left(-4\right)+8+\left(-3\right)}=3^{2-4+8+3}=3^9=19683\)
d)
\(3^2\cdot2^5\cdot\left(\frac{3}{2}\right)^{-2}\)
\(=9\cdot32\cdot12\) \(=288\cdot12=3456\)
Câu c) kết quả phải là \(9\) nhé mấy bạn.
Xin lỗi mình sửa lại câu c)
\(3^{2+\left(-4\right)+8+\left(-3\right)}=3^{2-4+8-3}=3^3\)
Mong bạn thông cảm !
