Class 9 Quiz Level 3 (Difficult) – Number System

Total questions: 10

$ \displaystyle \text{If }a=2+\sqrt{3}\text{ and }b=2-\sqrt{3}\text{ then the value of }{{a}^{2}}+{{b}^{2}}\text{ is}:$

Topic: Real Numbers

Deselect Answer

None

$\displaystyle x=3+\sqrt{2},\text{ then }{{x}^{2}}-6x+7\text{ is}$

Topic: Real Numbers

Deselect Answer

-1

None

$ \displaystyle \text{If }a=2+\sqrt{5}\text{ and }b=2-\sqrt{5},\text{then the value of }{{a}^{2}}+{{b}^{2}}\text{ is}:$

Topic: Real Numbers

Deselect Answer

None

The product of $ \displaystyle \left( {5+\sqrt{7}} \right)$ and $ \displaystyle \left( {5-\sqrt{7}} \right)$ is:

Topic: Real Numbers

Deselect Answer

None

$ \displaystyle The\text{ }value\text{ }of~\frac{1}{{\sqrt{5}+2}}\text{ is:}$

Topic: Real Numbers

Deselect Answer

$ \displaystyle \sqrt{5}-2$

$ \displaystyle \frac{{\left( {\sqrt{5}-2} \right)}}{3}$

$ \displaystyle \frac{{\left( {2-\sqrt{5}} \right)}}{3}$

$ \displaystyle \frac{{\left( {2+\sqrt{5}} \right)}}{3}$

None

$ \displaystyle If\ \sqrt{a}\text{ }=\text{ }\frac{7}{4}\text{ },\text{ then a is}:$

Topic: Real Numbers

Deselect Answer

$ \displaystyle \frac{{49}}{{16}}$

$ \displaystyle \frac{{28}}{{16}}$

$ \displaystyle \frac{{25}}{{9}}$

$ \displaystyle \frac{{16}}{{9}}$

None

$\displaystyle \text{If }x=3+\sqrt{5},\text{ then the }x-\frac{1}{x}\text{ is :}$

Topic: Real Numbers

Deselect Answer

$ \displaystyle \sqrt{5}-2$

$ \displaystyle \frac{{2-~2\surd 5~}}{{4~}}$

$ \displaystyle \frac{{9~+~5\surd 5~}}{{4~}}$

$ \displaystyle 4$

None

$ \displaystyle \text{If }x\text{ }=\text{ }2+\sqrt{5},\text{ }then\text{ }{{x}^{2}}-\text{ }4x\text{ }-\text{ }1\text{ }is:$

Topic: Real Numbers

Deselect Answer

-1

None

$ \displaystyle if\text{ }a\text{ }=\text{ }4\text{ }+\sqrt{3},\text{ }then\text{ }\frac{{1\text{ }}}{a}\text{ }is:$

Topic: Real Numbers

Deselect Answer

$ \displaystyle 4~-~\surd 3$

$ \displaystyle \frac{{4~-~\sqrt{3}}}{{13}}$

$ \displaystyle 2\text{ }-\text{ }2\sqrt{2}$

$ \displaystyle \frac{{4+~\sqrt{3}}}{{13}}$

None

10.

$ \displaystyle \text{if}\ a=3+\sqrt{7}\ and\ b=3-\sqrt{7},\text{then the value of }{{\text{a}}^{2}}+{{b}^{2}}\ is:$

Topic: Real Numbers

Deselect Answer

None

1 out of 10

Class 9 Quiz Level 3 (Difficult) – Number System

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