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If x =1-sqrt(2) find the value of (x-(1)...

If x =1`-sqrt(2)` find the value of `(x-(1)/(x))^(3)`

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To solve the given problem, we need to find the value of \((x - \frac{1}{x})^3\) where \(x = 1 - \sqrt{2}\). ### Step-by-Step Solution: 1. **Calculate \(x - \frac{1}{x}\):** \[ x - \frac{1}{x} = 1 - \sqrt{2} - \frac{1}{1 - \sqrt{2}} \] 2. **Rationalize the denominator of \(\frac{1}{1 - \sqrt{2}}\):** \[ \frac{1}{1 - \sqrt{2}} \times \frac{1 + \sqrt{2}}{1 + \sqrt{2}} = \frac{1 + \sqrt{2}}{(1 - \sqrt{2})(1 + \sqrt{2})} \] 3. **Simplify the denominator using the difference of squares formula:** \[ (1 - \sqrt{2})(1 + \sqrt{2}) = 1^2 - (\sqrt{2})^2 = 1 - 2 = -1 \] So, \[ \frac{1 + \sqrt{2}}{-1} = -(1 + \sqrt{2}) = -1 - \sqrt{2} \] 4. **Substitute back into the expression:** \[ x - \frac{1}{x} = 1 - \sqrt{2} - (-1 - \sqrt{2}) = 1 - \sqrt{2} + 1 + \sqrt{2} \] Simplify: \[ x - \frac{1}{x} = (1 + 1) + (-\sqrt{2} + \sqrt{2}) = 2 \] 5. **Calculate \((x - \frac{1}{x})^3\):** \[ (x - \frac{1}{x})^3 = 2^3 = 8 \] ### Final Answer: \[ (x - \frac{1}{x})^3 = 8 \]
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ICSE-RATIONAL AND IRRATIONAL NUMBERS -EXERCISE 1 (C)
  1. Find the values of a and b in each of the (5+3sqrt(2))/(5-3sqrt(2)...

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  2. Simplify : (22)/(2sqrt(3)+1)+(17)/(2sqrt(3)-1)

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  3. Simplify : (sqrt(2))/(sqrt(6)-sqrt(2))- (sqrt(3))/(sqrt(6)+sqrt(2))

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  4. If x =(sqrt(5)-2)/(sqrt(5)+2) and y = (sqrt(5)+2)/(sqrt(5)-2) : find :...

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  5. If x =(sqrt(5)-2)/(sqrt(5)+2) and y = (sqrt(5)+2)/(sqrt(5)-2) : find :...

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  6. If x =(sqrt(5)-2)/(sqrt(5)+2) and y = (sqrt(5)+2)/(sqrt(5)-2) : find :...

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  7. If x =(sqrt(5)-2)/(sqrt(5)+2) and y = (sqrt(5)+2)/(sqrt(5)-2) : find :...

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  8. If m = (1)/(3-2sqrt(2)) and n = (1)/(3+2sqrt(2)) find : (i) m^(2) (...

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  9. If x=2sqrt(3)+2sqrt(2) find : (1)/(x)

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  10. If x=2sqrt(3)+2sqrt(2) find : x+(1)/(x)

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  11. If x=2sqrt(3)+2sqrt(2) find : (x+(1)/(x))^(2)

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  12. If x =1-sqrt(2) find the value of (x-(1)/(x))^(3)

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  13. If x = 5-2sqrt(6) find : x^(2)+ (1)/(x^(2))

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  14. Show that : (1)/(3-2sqrt(2))- (1)/(2sqrt(2)-sqrt(7)) + (1)/(sqrt(7)-sq...

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  15. Rationalize the denominator of : (1)/(sqrt(3)-sqrt(2)+1)

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  16. If sqrt(2)= 1.4 and sqrt(3) = 1.7 find the value of each of the corre...

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  17. If sqrt(2)= 1.4 and sqrt(3) = 1.7 find the value of each of the corre...

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  18. If sqrt(2)= 1.4 and sqrt(3) = 1.7 find the value of each of the corre...

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  19. Evalutate : (4-sqrt(5))/(4+sqrt(5))+ (4+sqrt(5))/(4-sqrt(5))

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  20. If (2+sqrt(5))/(2-sqrt(5)) =x and (2-sqrt(5))/(2+sqrt(5)) =y , find th...

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