\(a,5\cdot5\cdot5\cdot5=5^4\\b,9\cdot9\cdot9\cdot9\cdot9\cdot9\cdot9=9^7\\c,7\cdot7\cdot7\cdot7\cdot7=7^5\\d,a\cdot a\cdot a\cdot a\cdot a\cdot a\cdot a\cdot a=a^8\)

a/ 5⁴

b/9⁷

c/7⁵

d/a⁸

\(a\))\(5.5.5.5=5^4\) 

\(b\))\(9.9.9.9.9.9.9=9^7\) 

\(c\))\(7.7.7.7.7=7^5\)

\(d\))\(a.a.a.a.a.a.a.a=a^8\)

a) \(2^{36}\)

b) \(3^{30}\)

c) \(3^9\)

d) \(2^{18}\)

a) 4⁸.2²⁰=(2²)⁸.2²⁰=2¹⁶.2²⁰=2³⁶

b) 9¹².27²=(3²)¹².(3³)²=3²⁴.3⁶=3³⁰

c) 3⁶.3².3=3⁹

d) 4⁵.16²=(2²)⁵.(2⁴)²=2¹⁰.2⁸=2¹⁸

Đáp án: A

5.5.5.5 =  5 4

MIK SỬA LẠI ĐỀ CÂU B

a) \(27^5:81^3=\left(3^3\right)^5:\left(3^4\right)^3=3^{15}:3^{12}=3^3\)

b) \(3^9:81^3=3^9:\left(3^4\right)^3=3^9:3^{12}=3^{-3}\)

a) \(\left(3^3\right)^5:\left(3^4\right)^3\)

= \(3^{15}:3^{12}\)

= \(3^3\)

a) \(27^5:81^3=3^{15}:3^{12}=3^3\)

b) \(3^9:81^3=3^9:3^{12}=\dfrac{1}{3^3}=\left(\dfrac{1}{3}\right)^3\)

a) 3.3^4.3^5 = 3^10

b) 7^3 : 7^2 : 7 = 7^1

c) (x^4)^3 = x^12

\(25^2:100^0=\left(5^2\right)^2:1=5^4\\ 30^3:30^0=2^3.3^3.5^3:1=2^3.3^3.5^3\)

a) \({2^m}{.2^n}=\underbrace {2.2 \ldots .2}_{m{\rm{ }}}{\rm{ }}.\underbrace {2.2 \ldots .2}_{n{\rm{ }}}{\rm{ }}\) = 2^m+n

b) \({3^m}:{3^n}=(\underbrace {3.3 \ldots .3}_{m{\rm{ }}}{\rm{ }}):(\underbrace {3.3 \ldots .3}_{n{\rm{ }}}{\rm{ }})\) = 3^m-n  với \(m \ge n\)

a) 9 . 9 . 9 . 9 . 9 = 9⁵

b) 10 . 10 . 10 . 10 = \(10^4\)

c) 5.5.5.25=5.5.5.5.5=\(5^5\)      

d) a.a.a.a.a.a=\(a^6\)

a) 9.9.9.9.9=9⁵                   b) 10. 10. 10. 10=10⁴

c) 5.5.5.25=5.5.5.5.5=5⁵                      d) a.a.a.a.a.a=a⁶

a. \(3^4.3^5=3^9\)

\(16.2^9=2^4.2^9=2^{13}\)

\(16.32=2^4.2^5=2^9\)

b. \(12^8.12=12^9\)

\(243:3^4=3^5:3^4=3\)

\(10^9:10000=10^9:10^4=10^5\)

c. \(4.8^6.2.8^3=2^2.2^{18}.2.2^9=2^{30}\)

\(12^2.2.12^3.6=12^2.12.12^3=12^6\)

\(6^3.2.6^4.3=6^3.6.6^4=6^8\)

he

a. 

16.29=24.29=21316.29=24.29=213

b. 

c. 4.86.2.83=22.218.2.29=2304.86.2.83=22.218.2.29=230