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If x=7-4sqrt3 then find the value of sqr...

If `x=7-4sqrt3` then find the value of `sqrtx+1/sqrtx`

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To find the value of \(\sqrt{x} + \frac{1}{\sqrt{x}}\) given \(x = 7 - 4\sqrt{3}\), we can follow these steps: ### Step 1: Calculate \( \sqrt{x} + \frac{1}{\sqrt{x}} \) We know that: \[ \sqrt{x} + \frac{1}{\sqrt{x}} = a + b \] where \(a = \sqrt{x}\) and \(b = \frac{1}{\sqrt{x}}\). ### Step 2: Square the expression To simplify the calculation, we can square the expression: \[ \left(\sqrt{x} + \frac{1}{\sqrt{x}}\right)^2 = x + \frac{1}{x} + 2 \] ### Step 3: Find \(x + \frac{1}{x}\) We need to calculate \(x + \frac{1}{x}\). We already have \(x = 7 - 4\sqrt{3}\). Now, we will find \(\frac{1}{x}\). ### Step 4: Calculate \(\frac{1}{x}\) To find \(\frac{1}{x}\), we rationalize: \[ \frac{1}{x} = \frac{1}{7 - 4\sqrt{3}} \cdot \frac{7 + 4\sqrt{3}}{7 + 4\sqrt{3}} = \frac{7 + 4\sqrt{3}}{(7 - 4\sqrt{3})(7 + 4\sqrt{3})} \] Calculating the denominator: \[ (7 - 4\sqrt{3})(7 + 4\sqrt{3}) = 7^2 - (4\sqrt{3})^2 = 49 - 48 = 1 \] Thus: \[ \frac{1}{x} = 7 + 4\sqrt{3} \] ### Step 5: Add \(x\) and \(\frac{1}{x}\) Now we can find \(x + \frac{1}{x}\): \[ x + \frac{1}{x} = (7 - 4\sqrt{3}) + (7 + 4\sqrt{3}) = 7 + 7 = 14 \] ### Step 6: Substitute back into the squared expression Now substitute back into the squared expression: \[ \left(\sqrt{x} + \frac{1}{\sqrt{x}}\right)^2 = 14 + 2 = 16 \] ### Step 7: Take the square root Finally, take the square root to find \(\sqrt{x} + \frac{1}{\sqrt{x}}\): \[ \sqrt{x} + \frac{1}{\sqrt{x}} = \sqrt{16} = 4 \] ### Final Answer Thus, the value of \(\sqrt{x} + \frac{1}{\sqrt{x}}\) is \(4\). ---

To find the value of \(\sqrt{x} + \frac{1}{\sqrt{x}}\) given \(x = 7 - 4\sqrt{3}\), we can follow these steps: ### Step 1: Calculate \( \sqrt{x} + \frac{1}{\sqrt{x}} \) We know that: \[ \sqrt{x} + \frac{1}{\sqrt{x}} = a + b \] ...
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NAGEEN PRAKASHAN ENGLISH-NUMBER SYSTEM-Exercise 1e
  1. Rationalise the denominator of each the following (i)(2)/(sqrt(3))" ...

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  2. Rationalise the denominator of each the of the following : (i)(1)/(3...

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  3. Simplify each of the following : (i)(sqrt(2)+1)/(sqrt(2)-1)+(sqrt(2)...

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  4. If sqrt(2)=1.414,sqrt(3)=1.732, find the value of the following : (i...

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  5. Find the value of a and b in each of the following (i)(3+sqrt(2))/(3...

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  6. If x=2+sqrt(3), then find : (i)(1)/(x)" "(ii)x+(1)/(x)" "(iii...

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  7. If x=3+2sqrt(2), then find : (i)(1)/(x)" "(ii)x+(1)/(x)" "(ii...

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  8. If x=(sqrt(3)+sqrt(2))/(sqrt(3)-sqrt(2)) and y=(sqrt(3)-sqrt(2))/(sqrt...

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  9. If a=1-sqrt(2),"then find the value of "(a-(1)/(a))^(3)

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  10. Evaluate 15/( sqrt10+sqrt20+sqrt40-sqrt5-sqrt80) is being given that s...

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  11. Write the following surds in descending order of their magnitudes : ...

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  12. If 25^(x-1)=5^(2x-1)-100, then find the value of x.

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  13. Which is greater sqrt(11)-sqrt(6) or sqrt(17)-sqrt(12) ?

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  14. If x=7-4sqrt3 then find the value of sqrtx+1/sqrtx

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  15. If x=2+sqrt(3), then find the value of x^(4)-4x^(3)+x^(2)+x+1.

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  16. Simplify sqrt(5+2sqrt(6))+sqrt(8-2sqrt(15))

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  17. If (9^n\ x\ 3^2\ x\ 3^n-\ 27^n)/(3^(3m)\ x\ 2^3)=1/(27) , prove that m...

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  18. Rationalise the denominator of : " "(2)/(sqrt(5)+sqrt(3)+2)

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