a) \(7^5.7^6=7^{5+6}=7^{11}\)
b) \(5^{20}.5=5^{20+1}=5^{21}\)
c) \(7^9:7=7^{9-1}=7^8\)
d) \(25^3.5^2=\left(5^2\right)^3.5^2=5^{2.3}.5^2=5^6.5^2=5^{6+2}=5^8\)
a. =7^11
b. =5^21
c. =7^8
d. =5^8
e. =a
f. =x^6
a/ 7 mu 5 . 7 mu 6 = 7 (mu 5 + mu 6 ) = 7 mu 11 b/ 5 mu 20 .5 = 5 ( mu 20 + mu 1 ) = 5 mũ 21 c/ 7 mũ 9 : 7 = 7 ( mu 9 - mu 1) = 7 mũ 8 d/ 25 mu 3 . 5 mũ 2 = ( 5.5 ) mu 3 . 5 mu 2 = 5mu 4 . 5mu 2 = 5 ( mu 4 mu 2 )= 5 mu6 e/ a mu 7 : a mu 6 = a ( mu 7- mũ 6 ) = a f/ x . x mũ 2 . x mũ 3 = x ( mu 1 + mu 2 + mu 3 ) = x mu 6
a)75. 76 =75+6 =711
b) 520. 5=520+1=521