7) (6^4)*(6^5)/ (6^9) = 6^(4+5)/(6^9) =(6^9)/(6^9) =1.
8) 36/( (6^0)*6²) = 36/( 1*36) = 36/36 =1.
9) 6*216 / 6³ =6*6³/6³ =6.
10) (5^9)/(5³*5^4) = (5^9)/(5^(3+4)) =(5^9)/(5^7) =5^(9-7) = 5^2 =25.
11) (5^5)*125/(5^9) =(5^5)*5³/(5^9) =5^(5+3)/(5^9) =(5^8)/(5^9)=(5^8)/(5*5^8) =1/5.
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a^1 ⇔a₁ ^2 ⇔a² , a^3 ⇔a³ ...(5^8)/(5^9) =5^(8 -9) = 5^(-1) =1/(5^1) =1/5.