Tag: maths
Questions Related to maths
Which of the following is smallest?
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$\sqrt [4]{5}$
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$\sqrt [5]{4}$
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$\sqrt {4}$
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$\sqrt {3}$
Let us rewrite the given set of magnitudes $\sqrt [ 4 ]{ 5 } ,\sqrt [ 5 ]{ 4 } ,\sqrt { 4 },\sqrt {3}$ as follows:
Arrange the following surds in ascending order of their magnitudes: $\sqrt{5},\sqrt [ 3 ]{ 11 } ,2\sqrt [ 6 ]{ 3 } $
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$\sqrt [ 3 ]{ 11 } > \sqrt{5}< 2\sqrt [ 6 ]{ 3 } $
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$\sqrt [ 3 ]{ 11 } < \sqrt{5}< 2\sqrt [ 6 ]{ 3 } $
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$\sqrt [ 3 ]{ 11 } > \sqrt{5}> 2\sqrt [ 6 ]{ 3 } $
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$\sqrt [ 3 ]{ 11 } < \sqrt{5}> 2\sqrt [ 6 ]{ 3 } $
$\sqrt{5} = 5^{1/2}$
$\sqrt[3]{11} = 11^{1/3}$
$2\sqrt[6]{3} = \sqrt[6]{12}= 12^{1/6}$
L.C.M of the denominators of the exponents is 12.
So,
$\sqrt{5} = 5^{\frac{1}{2}\times\frac{6}{6}} = \sqrt [12]{5^6}=\sqrt[12]{15625}$
$\sqrt[3]{11} = 11^{\frac{1}{3}\times\frac{4}{4}} = \sqrt [12]{11^4} =\sqrt[12]{14641}$
$2\sqrt[6]{3} = \sqrt[6]{12}= 12^{\frac{1}{6}\times\frac{2}{2}} = \sqrt[12]{12^2} =\sqrt[12]{144}$
Hence, the Ascending order is $2\sqrt[6]{3}, \sqrt[3]{11},\sqrt{5}$
Write $\displaystyle \sqrt[4]{6},\sqrt{2},\sqrt[3]{4}$ in ascending order
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$\displaystyle \sqrt{2},\sqrt[4]{6}$ and $\displaystyle \sqrt[3]{4}$
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$\displaystyle \sqrt[4]{6}$, $\sqrt{2}$ and $\displaystyle \sqrt[3]{4}$
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$\displaystyle \sqrt{2}$, $\displaystyle \sqrt[3]{4}$ and $\sqrt[4]{6}$
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None of these
$\displaystyle 6^\cfrac 14,2^\cfrac 12,4^\cfrac 13$
The surds are of the order $4, 2$ and $3$ respectively The L.C.M. is $12$ So, we change each surd of the order $12$
The terms now are $\displaystyle \left ( 6^{3} \right )^\cfrac {1}{12},\left ( 2^{6} \right )^\cfrac{1}{12}$ and $\displaystyle \left ( 4^{4} \right )^\cfrac{1}{12}$
$\displaystyle \Rightarrow \left ( 216 \right )^\cfrac{1}{12},\left ( 64 \right )^\cfrac{1}{12}$ and $\displaystyle \left ( 256 \right )^\cfrac{1}{12}$
$\displaystyle \therefore $ Ascending order is $\displaystyle \sqrt{2},\sqrt[4]{6}$ and $\displaystyle \sqrt[3]{4}$
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True
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False
State true or false
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True
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False
Which is greater?
${ \left( \cfrac { 1 }{ 2 } \right) }^{ 1/2 } $ or ${ \left( \cfrac { 2 }{ 3 } \right) }^{ 1/3 } $
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${ \left( \cfrac { 2 }{ 3 } \right) }^{ 1/3 } $
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${ \left( \cfrac { 1 }{ 2 } \right) }^{ 1/2 } $
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Both are equal
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None of the above
$ \left(\dfrac{1}{2}\right)^{1/2} \; or \; \left(\dfrac{2}{3}\right)^{1/3}$
$= \left(\left(\dfrac{1}{2}\right)^{1/2}\right)^6 \; or \; \left(\left(\dfrac{2}{3}\right)^{1/3}\right)^6$
$= \left(\dfrac{1}{2}\right)^3 \; or \; \left(\dfrac{2}{3}\right)^2$
$= \left(\dfrac{1}{8}\right) \; or \; \left(\dfrac{4}{9}\right)$
= 0.125 or 0.44
Since, 0.44 is greater and so is $ \left(\dfrac{2}{3}\right)^{1/3}$
The correct descending order of the following surds is
$ \sqrt [3]{2}$, $\sqrt 3$, $\sqrt 4$, $\sqrt 5$
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$\sqrt 3$ > $\sqrt 4$ > $\sqrt 5$ > $\sqrt [3]{2}$
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$\sqrt 4$ > $\sqrt 5$ > $\sqrt [3]{2}$ > $\sqrt 3$
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$\sqrt 5$ > $\sqrt 4$ > $\sqrt 3$ > $\sqrt [3]{2}$
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$\sqrt [3]{2}$ > $\sqrt 4$ > $\sqrt 3$ > $\sqrt 5$
LCM of $3$ and $2$ is $6$.
Therefore, multiplying the index of all numbers by $6$.
${\sqrt [3]{2}}^6 = 2^\dfrac 63 = 2^2 = 4$
${\sqrt 3}^6 = 3^\dfrac 62 = 3^3 = 27$
${\sqrt 4}^6 = 4^ \dfrac 62 = 4^3 = 64$
${\sqrt 5}^6 = 5^{\dfrac 62} = 5^3 = 125$
$\therefore 125 > 64 > 27 > 4$
Which one of the following is an irrational number?
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$\sqrt[3]{-27}$
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$\sqrt{2}(3\sqrt{2}+2\sqrt{8})$
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$\dfrac{3\sqrt{18}}{2\sqrt{6}}$
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$\sqrt{\dfrac{1}{2}}\cdot\sqrt{\dfrac{25}{2}}$
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$\dfrac{2\sqrt{5}}{\sqrt{45}}$
Option A: $\sqrt [ 3 ]{ -27 } ={ (-3) }^{ 3\times \frac { 1 }{ 3 } }=-3$
Option B: $\sqrt { 2 } (3\sqrt { 2 } +2\sqrt { 8 } )=\sqrt { 2 } (3\sqrt { 2 } +4\sqrt { 2 } )=\sqrt { 2 } (7\sqrt { 2 } )=14$
Option C: $\dfrac { 3\sqrt { 18 } }{ 2\sqrt { 6 } } =\dfrac { 3\sqrt { 3 } }{ 2 } $
Option D: $\sqrt { \dfrac { 1 }{ 2 } } \sqrt { \dfrac { 25 }{ 2 } } =\dfrac { 5 }{ 2 } $
Option E: $\dfrac { 2\sqrt { 5 } }{ \sqrt { 45 } } =\dfrac { 2\sqrt { 5 } }{ 3\sqrt { 5 } } =\dfrac { 2 }{ 3 } $
Therefore, all are rational except option $C$.
Solve the following quadratic equation by completing the square: $ x^2+(\sqrt{3}+1)x+\sqrt{3}=0$
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$\left { \sqrt{3}, 1\right }$
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$\left { \sqrt{3}, 2\right }$
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$\left { \sqrt{3}, 3\right }$
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None of these
Given equation is $x^2-(\sqrt{3}+1)x+\sqrt{3}=0$
Zero degree polynomial is considered as
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variable
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coefficent
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constant
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zero
Zero degree polynomial is considered as constant.
Example: $p(x)= k$
Therefore, $k$ is constant.
The constant term in an expression or equation has a fixed value and does not contain variables.