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

If `x=2+sqrt(3)`, 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 for each part as follows: Given: \[ x = 2 + \sqrt{3} \] ### (i) Find \( \frac{1}{x} \) 1. Start with the expression: \[ \frac{1}{x} = \frac{1}{2 + \sqrt{3}} \] 2. To rationalize the denominator, multiply the numerator and denominator by the conjugate of the denominator: \[ \frac{1}{2 + \sqrt{3}} \cdot \frac{2 - \sqrt{3}}{2 - \sqrt{3}} = \frac{2 - \sqrt{3}}{(2 + \sqrt{3})(2 - \sqrt{3})} \] 3. Calculate the denominator using the difference of squares: \[ (2 + \sqrt{3})(2 - \sqrt{3}) = 2^2 - (\sqrt{3})^2 = 4 - 3 = 1 \] 4. Therefore, we have: \[ \frac{1}{x} = 2 - \sqrt{3} \] ### (ii) Find \( x + \frac{1}{x} \) 1. Substitute the values of \( x \) and \( \frac{1}{x} \): \[ x + \frac{1}{x} = (2 + \sqrt{3}) + (2 - \sqrt{3}) \] 2. Combine like terms: \[ = 2 + \sqrt{3} + 2 - \sqrt{3} = 4 \] ### (iii) Find \( x - \frac{1}{x} \) 1. Substitute the values of \( x \) and \( \frac{1}{x} \): \[ x - \frac{1}{x} = (2 + \sqrt{3}) - (2 - \sqrt{3}) \] 2. Simplify: \[ = 2 + \sqrt{3} - 2 + \sqrt{3} = 2\sqrt{3} \] ### (iv) Find \( x^2 + \frac{1}{x^2} \) 1. Use the identity: \[ x^2 + \frac{1}{x^2} = \left( x + \frac{1}{x} \right)^2 - 2 \] 2. Substitute the value of \( x + \frac{1}{x} \): \[ x^2 + \frac{1}{x^2} = 4^2 - 2 = 16 - 2 = 14 \] ### Summary of Results: 1. \( \frac{1}{x} = 2 - \sqrt{3} \) 2. \( x + \frac{1}{x} = 4 \) 3. \( x - \frac{1}{x} = 2\sqrt{3} \) 4. \( x^2 + \frac{1}{x^2} = 14 \)

To solve the problem step by step, we will find the values for each part as follows: Given: \[ x = 2 + \sqrt{3} \] ### (i) Find \( \frac{1}{x} \) 1. Start with the expression: ...
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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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