Câu 1:
`729 = 3^6`
`729 = 9^3`
`729 = 27^2`
Câu 2:
a. `2^5 × 8^4 = 2^5 × 2^12 = 2^17`
b. `25^6 × 125^3 = 125^4 × 125^3 = 125^7`
c. `625^5 : 25^7 = 25^10 : 25^7 = 25^3`
d. `12^3 × 3^3 = 36^3`
Câu 3:
a. `6^(3^1) = 6^3 = 216`
b. `3^(2^3) = 3^8 = 6561`
c. `7^(1^(2^(3^4))) = 7^1 = 7`
d. `2003^(2^(0^(1^0))) = 2003^(1^1) = 2003`
Câu 4:
a.
`2^x - 15 = 17`
`⇔2^x = 32`
`⇔2^x = 2^5`
`⇒x = 5`
b.
`(7x - 11)^3 = 2^5 × 5^2 + 200`
`⇔(7x - 11)^3 = 800 + 200`
`⇔(7x - 11)^3 = 1000`
`⇔(7x - 11)^3 = 10^3`
`⇔7x - 11 = 10`
`⇔7x = 21`
`⇔x = 3`
Câu 5:
a.
`x^10 = 1^x`
`⇔x^10 = 1`
`⇔`\(\left[ \begin{array}{l}x=0\\x=1\end{array} \right.\)
Vậy `(x, y) = (0; 1)`
b.
`x^10 = x`
`⇔x^10 - x = 0`
`⇔`\(\left[ \begin{array}{l}x=0\\x=1\end{array} \right.\)
Vậy `(x, y) = (0; 1)`
c.
`(2x - 15)^5 = (2x - 15)^3`
`⇔(2x - 15)^2 = 1`
`⇔2x - 15 = 1`
`⇔2x = 16`
`⇔x = 8`
Vậy `x = 8`
Câu 6:
`A=(11*3^22*3^7-9^15)/((2*3^14)^2)`
`=(11*3^29-9^15)/(2^2*3^38)`
`=(11*3^29-3^30)/(2^2*3^28)`
`=(11*3^29-3^29*3)/(4*3^28)`
`=((11-3)*3^29)/(4*3^28)`
`=(8*3^29)/(4*3^28)`
`=(8*3)/4=6`
Vậy `A = 6`