Question

please help me please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please help me

Answer 1

a

Step-by-step explanation

Step 1

remember some laws of exponents

`\begin{gathered} a^m\cdot a^n=a^(m+n) \\ (a^m)^n=a^(m\cdot n) \\ a^(-m)=(1)/(a^m) \end{gathered}`

then

`2^(-5)\cdot2^8=2^(-5+8)=2^3=8`

now, check the answer options

`\begin{gathered} a)(2^2)/(2^(-1))=2^2\cdot(1)/(2^(-1))=4\cdot2=8 \\ b)(2^3)^(-1)=2^(3\cdot-1)=2^(-3)=(1)/(2^3)=(1)/(8) \\ c)(2^(-2))/(2^(-1))=(2^1)/(2^2)=(2)/(4)=(1)/(2) \\ d)(2^(-1))^3=2^(1-\cdot3)=2^(-3)=(1)/(2^3)=(1)/(8) \end{gathered}`

so, the answer is a