Math, asked by lpmc, 1 year ago

if X = 8 + root 60 then root X + 1 / root X = ?

Answers

Answered by ARoy
23
x=8+√60
=8+√4×15
=5+3+2√15
=(√5)²+2.√5.√3+(√3)²
=(√5+√3)²
∴, √x=√5+√3
1/√x=1/(√5+√3)
=(√5-√3)/(√5+√3)(√5-√3)
=(√5-√3)/{(√5)²-(√3)²}
=(√5-√3)/(5-3)
=(√5-√3)/2
√x+1/√x
=√5+√3+(√5-√3)/2
=(2√5+2√3+√5-√3)/2
=(3√5+√3)/2
=√3(√3.√5+1)/2
=√3(1+√15)/2
Answered by pinquancaro
11

Answer:

\sqrt{x}+\frac{1}{\sqrt{x}}=\frac{3\sqrt{5}+\sqrt{3}}{2}

Step-by-step explanation:

Given : x=8+\sqrt{60}

To find : \sqrt{x}+\frac{1}{\sqrt{x}}

Solution :

First we find the square root of x,

x=8+\sqrt{60}

x=8+\sqrt{4\times 15}

x=5+3+2\sqrt{15}

x=(\sqrt{5})^2+(\sqrt{3})^2+2\times \sqrt{5}\times \sqrt{3}

x=(\sqrt{5}+\sqrt{3})^2

\sqrt{x}=\sqrt{5}+\sqrt{3}

Now, we find \frac{1}{\sqrt{x}}

\frac{1}{\sqrt{x}}=\frac{1}{\sqrt{5}+\sqrt{3}}

Rationalize,

\frac{1}{\sqrt{x}}=\frac{1}{\sqrt{5}+\sqrt{3}}\times \frac{\sqrt{5}-\sqrt{3}}{\sqrt{5}-\sqrt{3}}

\frac{1}{\sqrt{x}}=\frac{\sqrt{5}-\sqrt{3}}{(\sqrt{5})^2-(\sqrt{3})^2}

\frac{1}{\sqrt{x}}=\frac{\sqrt{5}-\sqrt{3}}{5-3}

\frac{1}{\sqrt{x}}=\frac{\sqrt{5}-\sqrt{3}}{2}

Substitute in the expression,

\sqrt{x}+\frac{1}{\sqrt{x}}=\sqrt{5}+\sqrt{3}+\frac{\sqrt{5}-\sqrt{3}}{2}

\sqrt{x}+\frac{1}{\sqrt{x}}=\frac{2\sqrt{5}+2\sqrt{3}+\sqrt{5}-\sqrt{3}}{2}

\sqrt{x}+\frac{1}{\sqrt{x}}=\frac{3\sqrt{5}+\sqrt{3}}{2}

Therefore, \sqrt{x}+\frac{1}{\sqrt{x}}=\frac{3\sqrt{5}+\sqrt{3}}{2}

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