Tag: maths

Questions Related to maths

Which of the following represents the power of product rule?

  1. $(x\times y)^{a} = x^{a} \times y$

  2. $(x\times y)^{a} = x \times y^{a}$

  3. $(x\times y)^{a} = x^{a} + y^{a}$

  4. $(x\times y)^{a} = x^{a} \times y^{a}$


Correct Option: D
Explanation:

If the product of the bases is powered  by the same exponent, 

then the result is multiplication of all the bases, 
each powered by the given exponent.
$\therefore (x\times y)^{a} = x^{a} \times y^{a}$.
So, option $D$ is correct.

Evaluate: $\left (\dfrac {2^{3}}{3^{3}} \right )^{2}$

  1. $\dfrac {64}{729}$

  2. $\dfrac {729}{64}$

  3. $\dfrac {32}{243}$

  4. $\dfrac {243}{32}$


Correct Option: A
Explanation:

$\left (\dfrac {2^{3}}{3^{3}} \right )^{2} = \dfrac {2^{6}}{3^{6}} = \dfrac {64}{729}$


So, option $A$ is correct.

On simplifying  $\displaystyle 3^{3}\times a^{3}\times b^{3}$, we get

  1. $\displaystyle \left ( 3ab \right )^{3} $

  2. $\displaystyle 3\left ( ab \right )^{3} $

  3. $\displaystyle \left ( 27ab \right )^{3} $

  4. None of these


Correct Option: A
Explanation:

$\displaystyle 3^{2}\times a^{3}\times b^{3}=\left ( 3ab \right )^{3}$.

This is the power of product law of exponents.
So, option $A$ is correct.

Find the value of: $\displaystyle \left [ \left ( -1 \right )^{2}\times \left ( -1 \right )^{3}\times \left ( -1 \right )^{4} \right ]^{6}$

  1. $3$

  2. $-1$

  3. $1$

  4. $\displaystyle 3^{6}$


Correct Option: C
Explanation:

$\displaystyle \left [ \left ( -1 \right )^{2}\times \left ( -1 \right )^{3}\times \left ( -1 \right )^{4} \right ]^{6}$

=$\displaystyle \left [ \left ( -1 \right )^{12}\times \left ( -1 \right )^{18}\times \left ( -1 \right )^{24} \right ]$

=$\displaystyle \left [ 1\times 1\times 1 \right ]$ =$1$
So, option $C$ is correct.

The value of $\displaystyle \left (-4  \right ) ^{3}\times \left ( -3 \right )^{3}$ is _____?

  1. $\displaystyle 12^{3}$

  2. $\displaystyle -12^{3}$

  3. $\displaystyle -7^{3}$

  4. $\displaystyle 7^{3}$


Correct Option: A
Explanation:

$\displaystyle \left ( -4 \right )^{3}\times \left ( -3 \right )^{3}=\left ( -4\times -3 \right )^{3}$

$=\displaystyle \left ( -4\times -3 \right )^{3}$
$=\displaystyle 12^3$

Find the expression which equals $\displaystyle a^{x}\times b^{x}$.

  1. $\left [\displaystyle a^{x}+ b^{x} \right ]$

  2. $\displaystyle \left ( ab\right )^x $

  3. $\displaystyle \left (a+b \right )^{x} $

  4. $\displaystyle a\left ( b \right )^{x} $


Correct Option: B
Explanation:

$\displaystyle a^{x}\times b^{x}=\left ( ab \right )^{n}$

So, option $B$ is correct.

Evaluate: $\displaystyle 5^{2}\times 3^{2} $

  1. $\displaystyle \left (53 \right ) ^{2}$

  2. $\displaystyle \left (15 \right ) ^{2}$

  3. $\displaystyle \left (8 \right ) ^{2}$

  4. $60$


Correct Option: B
Explanation:

$\displaystyle 5^{2}\times 3^{2}=\left ( 15 \right )^{2}$

So, option $B$ is correct.

Evaluate: $\displaystyle \left [ \left ( 4 \right )^{\tfrac{1}{4}}\times \left ( 2 \right )^{\tfrac{1}{2}}\times \left ( 5 \right )^{\tfrac{1}{5}} \right ]^{0}$

  1. $40$

  2. $0$

  3. $1$

  4. $10$


Correct Option: C
Explanation:

=$\displaystyle \left [ \left ( 4 \right )^{\tfrac{1}{4}}\times \left ( 2 \right )^{\tfrac{1}{2}} \times \left ( 5 \right )^{\tfrac{1}{2}}\right ]^{0}$

=$\displaystyle 4^{0}\times 2^{0}\times 5^{0}$
=$\displaystyle 1\times 1\times 1$
=$1$
So, option $C$ is correct.

The value of $\displaystyle \left [ \left ( \frac{-2}{5} \right )^{3} \right ]^{2}$ is:

  1. $\displaystyle -\frac{2}{5}$

  2. $\displaystyle -\frac{32}{3125}$

  3. $\displaystyle\frac{64}{15625}$

  4. $\displaystyle -\frac{64}{15625}$


Correct Option: C
Explanation:

$\displaystyle \left [ \left ( \frac{-2}{5} \right )^{3} \right ]^{2}=\left ( \frac{-2}{5} \right )^{6}=\frac{\left ( -2 \right )^{6}}{5^{6}}=\frac{64}{15625}$

Hence, option $C$ is correct.

Simplify: $\displaystyle \left ( -a \right )^{9}\times \left ( -b \right )^{9}$ 

  1. $\displaystyle \left ( ab \right )^{9}$

  2. $\displaystyle \left ( -ab \right )^{9}$

  3. $\displaystyle -\left ( ab \right )^{9}$

  4. $\displaystyle \left ( a-b \right )^{9}$


Correct Option: A
Explanation:

$(-a)^9 \times (-b)^9 = [ -a \times -b]^9$


= $ [ a \times b]^9$

=$ (ab)^9$
So, option $A$ is correct.