`#Sad`
`\text{Bài}` `1:`
`a,`
`7^5 : 7^2 = 7^3`
`b,`
`5^(12) : 5^7 = 5^5`
`c,`
`x^(17) : x^(12) = x^5`
`d,`
`16^3 : 4^2 = 16^3 : 16 = 16^2`
`e,`
`25^2 : 5^2 = 25^2 : 25 = 25`
`\text{Bài}` `2:`
`a,`
`3^x = 1`
`⇔3^x = 1^0`
`⇔x = 0`
`\text{Vậy}` `x=0`
`b,`
`x^4 = 1`
`⇔x^4 = 1^4`
`⇔x = 1`
`\text{Vậy}` `x=1`
`c,`
`2^x = 16`
`⇔2^x = 2^4`
`⇔x = 4`
`\text{Vậy }` `x=4`
`d,`
`x^2 = 9`
`⇔x^2 = 3^2`
`⇔x = 3`
`\text{Vậy }` `x=3`
`\text{Bài}` `3:`
`a,`
`4^n = 4^3 . 4^5`
`⇔4^n = 4^8`
`⇔n = 8`
`\text{Vậy}` `n=8`
`b,`
`25^n = 5^2 . 5^4`
`⇔25^n = 5^6`
`⇔25^n = 25^3`
`⇔n = 3`
`\text{Vậy}` `n=3`
\(\left[ \begin{array}{l}x^2\\x=-1\end{array} \right.\)
