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

If `x=3+2sqrt(2)`, then find :
`(i)(1)/(x)" "(ii)x+(1)/(x)" "(iii)x-(1)/(x)" "(iv)x^(2)-(1)/(x^(2))`

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To solve the problem step by step, we will find the values of \( \frac{1}{x} \), \( x + \frac{1}{x} \), \( x - \frac{1}{x} \), and \( x^2 - \frac{1}{x^2} \) given that \( x = 3 + 2\sqrt{2} \). ### Step 1: Find \( \frac{1}{x} \) Given \( x = 3 + 2\sqrt{2} \), we need to find \( \frac{1}{x} \). To rationalize the denominator, we multiply the numerator and the denominator by the conjugate of the denominator: \[ \frac{1}{x} = \frac{1}{3 + 2\sqrt{2}} \cdot \frac{3 - 2\sqrt{2}}{3 - 2\sqrt{2}} = \frac{3 - 2\sqrt{2}}{(3 + 2\sqrt{2})(3 - 2\sqrt{2})} \] Now, calculate the denominator: \[ (3 + 2\sqrt{2})(3 - 2\sqrt{2}) = 3^2 - (2\sqrt{2})^2 = 9 - 8 = 1 \] Thus, \[ \frac{1}{x} = 3 - 2\sqrt{2} \] ### Step 2: Find \( x + \frac{1}{x} \) Now, we calculate \( x + \frac{1}{x} \): \[ x + \frac{1}{x} = (3 + 2\sqrt{2}) + (3 - 2\sqrt{2}) = 3 + 3 + 2\sqrt{2} - 2\sqrt{2} = 6 \] ### Step 3: Find \( x - \frac{1}{x} \) Next, we calculate \( x - \frac{1}{x} \): \[ x - \frac{1}{x} = (3 + 2\sqrt{2}) - (3 - 2\sqrt{2}) = 3 - 3 + 2\sqrt{2} + 2\sqrt{2} = 4\sqrt{2} \] ### Step 4: Find \( x^2 - \frac{1}{x^2} \) We can use the identity \( x^2 - \frac{1}{x^2} = (x - \frac{1}{x})(x + \frac{1}{x}) \). From Steps 2 and 3, we have: - \( x + \frac{1}{x} = 6 \) - \( x - \frac{1}{x} = 4\sqrt{2} \) Now, substitute these values into the identity: \[ x^2 - \frac{1}{x^2} = (4\sqrt{2})(6) = 24\sqrt{2} \] ### Summary of Results 1. \( \frac{1}{x} = 3 - 2\sqrt{2} \) 2. \( x + \frac{1}{x} = 6 \) 3. \( x - \frac{1}{x} = 4\sqrt{2} \) 4. \( x^2 - \frac{1}{x^2} = 24\sqrt{2} \)

To solve the problem step by step, we will find the values of \( \frac{1}{x} \), \( x + \frac{1}{x} \), \( x - \frac{1}{x} \), and \( x^2 - \frac{1}{x^2} \) given that \( x = 3 + 2\sqrt{2} \). ### Step 1: Find \( \frac{1}{x} \) Given \( x = 3 + 2\sqrt{2} \), we need to find \( \frac{1}{x} \). To rationalize the denominator, we multiply the numerator and the denominator by the conjugate of the denominator: \[ ...
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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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