α2.a5 = a2+5 = a7
a5:a = a5-1= a4
245:(26:32) = 245:(26: 25) = 245: 2 = 244
525.25 = 525. 52= 527
222:4 =222: 22 = 220
α2.a5 = a2+5 = a7
a5:a = a5-1= a4
245:(26:32) = 245:(26: 25) = 245: 2 = 244
525.25 = 525. 52= 527
222:4 =222: 22 = 220
38.320.:27 = 38.320: 33= 331
--tho-- là me
Lời giải:
$a^2.a^5=a^{2+5}=a^7$
$a^5:a=a^{5-1}=a^4$ (đk $a\neq 0$)
$2^{45}:(2^6:32)=2^{45}:(2^6:2^5)=2^{45}:2=2^{45-1}=2^{44}$
$5^{25}.25=5^{25}.5^2=5^{25+2}=5^{27}$
$2^{22}:4=2^{22}:2^2=2^{22-2}=2^{20}$
$3^8.3^{20}:27=3^{8+20}:3^3=3^{28}:3^3=3^{28-3}=3^{25}$
