Question : If $x=3 - 2\sqrt2$, then $\sqrt x+(\frac{1}{\sqrt x})$ is equal to:
Option 1: $0$
Option 2: $1$
Option 3: $2$
Option 4: $2\sqrt2$
Correct Answer: $2\sqrt2$
Solution : Given: $x = 3 - 2\sqrt{2}$ According to the question, Let $y = \sqrt{x}+\frac{1}{\sqrt{x}}$ Squaring both sides, $y^2 = x + \frac{1}{x}+2$ Put the value $x$, $y^2 = 3 - 2\sqrt{2} + \frac{1}{3-2\sqrt{2}} + 2$ or, $y^2 = 3 - 2\sqrt{2} + \frac{1}{3-2\sqrt{2}} × \frac{3+\sqrt{2}}{3 + \sqrt{2}} + 2$ or, $y^2 = 5 - 2\sqrt{2} + 3 + 2\sqrt{2}$ or, $y^2 = 8$ or, $y = 2\sqrt{2}$ Hence, the correct answer is $2\sqrt{2}$.
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Question : If $x^2+\frac{1}{x^2}=\frac{7}{4}$ for $x>0$; then what is the value of $x+\frac{1}{x}$?
Option 1: $2$
Option 2: $\frac{\sqrt{15}}{2}$
Option 3: $\sqrt{5}$
Option 4: $\sqrt{3}$
Question : If $x^2+\frac{1}{x^2}=\frac{7}{4}$ for $x>0$, what is the value of $(x^3+\frac{1}{x^3})$?
Option 1: $\frac{3\sqrt{3}}{5}$
Option 2: $\frac{3\sqrt{15}}{5}$
Option 3: $\frac{3\sqrt{15}}{8}$
Option 4: $\frac{3\sqrt{5}}{8}$
Question : If $\sqrt{x}+\frac{1}{\sqrt{x}}=3, x>0$, then $x^2\left(x^2-47\right)=?$
Option 2: $2$
Option 3: $-2$
Option 4: $-1$
Question : If $a= \frac{\sqrt{x+2}+\sqrt{x-2}}{\sqrt{x+2}-\sqrt{x-2}}$, then the value of $(a^{2}-ax)$ is:
Option 1: 1
Option 2: 2
Option 3: –1
Option 4: 0
Question : If $p = 5 + 2\sqrt6$, then $\frac{\sqrt p - 1}{\sqrt p}$ is:
Option 1: $1 + \sqrt2 - \sqrt3$
Option 2: $1 - \sqrt2 + \sqrt3$
Option 3: $ - 1 + \sqrt2 - \sqrt3$
Option 4: $1 - \sqrt2 - \sqrt3$
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