#1 What is the value of the expression 7–3? Answers: A. –21 B. - 1/343 C.1/343 D. 343
#2What is the value of the expression 1/5^-5? Answers: A. 1/3125 B.1/25 C.25 D. 3125
#3What is the value of the expression 2/4^-3?Answers: A. 1/32 B. 1/6 C.128 D.256
#4 What value of k solves the equation? K^-2=1/64 Answers: A.1/8 B. 8 C. 32 D. 128
#5 What value of n solves the equation? 4^N= 1/64 Answers: A. –3 B. 3 C. 16 D. 256
\(\#1\ \ \ 7^{-3}= \frac{1}{7^3} = \frac{1}{343}\ \ \ \Rightarrow\ \ \ Ans.\ C\\ \\ \#2\ \ \ \frac{1}{5^{-5}}=5^5=3125\ \ \ \Rightarrow\ \ \ \ Ans.\ D\\ \\ \#3\ \ \ \frac{2}{4^{-3}}=2\cdot4^{3}=2\cdot 64=128\ \ \ \Rightarrow\ \ \ Ans.\ C\\ \\\#4\ \ \ K^{-2}= \frac{1}{64} \ \ \Rightarrow\ \ \ \frac{1}{K^2} = \frac{1}{64}\\\\ .\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ K^2=64 \ \ \Rightarrow\ \ K=8\ \ \Rightarrow\ \ Ans.\ B\\ \\\)
\(\#5\ \ \ 4^N= \frac{1}{64}\ \ \Rightarrow\ \ \ 4^N=4^{-3}\ \ \ \Rightarrow\ \ \ N=-3\ \ \ \Rightarrow\ \ \ Ans.\ A\)
First question
The given expression is
\(7^{-3}\)
Which can also be written as
\(\frac{1}{7^3}= \frac{1}{343}\)
Therefore the correct option is C.
2.
The given expression is
\(\frac{1}{5^{-5}}\)
Which can also be written as
\(5^5 = 3125\)
So the correct option is D
3.
The given expression is
\(\frac{2}{4^{-3}}\)
Which can also be written as
\(2*4^3 = 2* 64=128\)
And the correct option is C
4.
The given equation is
\(k^{-2} = \frac{1}{64} \\ k^2 = 64 \\ k^2 = 8^2 \\ k=8\)
So the correct option is B
5.
The given equation is
\(4^N = \frac{1}{64} \\ 4^N = 4^{-3} \\ N =-3\)
And the correct option is A .