Powers with Positive and Negative Exponents

Q.

The value of $[4^{-1}+3^{-1}+6^{-2}{]}^{-1}$ is ___.

1. $\frac{36}{22}$

2. $\frac{36}{20}$

3. $\frac{36}{11}$

4. $\frac{38}{22}$

Q.

Solve $2^{2x+2}-6\times 2^x+2=0$

1. $x=-1orx=0$

2. $x=-1orx=1$

3. $x=-1orx=2$

4. $x=-2orx=0$

Q.

Find the value of $(\frac{1}{15}{)}^{-2}$ + $(\frac{1}{13}{)}^{-2}$ + $(\frac{1}{12}{)}^{-2}$.

1. 41

2. 538

3. 0.226

4. 269

Q.

If $3^x=\frac{1}{81}$, then the value of $x$ is

1. -4

2. -2

3. 4

4. 2

Q.

If $a^{n+2}$ = $a^{2n-1}$, the value of n is :

1. 1

2. 2

3. 3

4. 0

Q.

${(-\frac{5}{7})}^{-5}$ is equal to :

1. ${\left(\frac{5}{7}\right)}^{-5}$

2. ${\left(\frac{7}{5}\right)}^{-5}$

3. ${(-\frac{7}{5})}^{-5}$

4. ${(-\frac{7}{5})}^5$

Q. $x^{-m}$ is equal to

1. $x^m$
   
   

2. $-x^m$
   

3. $\frac{1}{x^m}$
   

4. $\frac{-1}{x^m}$

Q.

Find the value of : $\frac{x^{a(b-c)}}{x^{b(a-c)}}÷(\frac{x^b}{x^a}{)}^c$

1. 0

2. b

3. a

4. 1

Q.

Express $8^{-2}$ as a exponent with base 2 :

1. $2^{-8}$

2. $8^{-4}$

3. $2^{-6}$

4. $2^{-4}$

Q.

$(-1{)}^{-3}$ is :

1. 1

2. -1

3. 0

4. 2