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Rationalise the denominator of each the ...

Rationalise the denominator of each the of the following :
`(i)(1)/(3+sqrt(5))" "(ii)(1)/(sqrt(5)-sqrt(3))" "(iii)(16)/(sqrt(41)+5)" "(iv)(30)/(5sqrt(3)+3sqrt(5))" "(v)(3-2sqrt(2))/(3+2sqrt(2))`

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Let's rationalize the denominators of the given expressions step by step. ### (i) Rationalizing \( \frac{1}{3 + \sqrt{5}} \) **Step 1:** Multiply the numerator and denominator by the conjugate of the denominator, which is \( 3 - \sqrt{5} \). \[ \frac{1}{3 + \sqrt{5}} \cdot \frac{3 - \sqrt{5}}{3 - \sqrt{5}} = \frac{3 - \sqrt{5}}{(3 + \sqrt{5})(3 - \sqrt{5})} \] **Step 2:** Simplify the denominator using the difference of squares formula \( (a + b)(a - b) = a^2 - b^2 \). \[ (3 + \sqrt{5})(3 - \sqrt{5}) = 3^2 - (\sqrt{5})^2 = 9 - 5 = 4 \] **Step 3:** Substitute back into the expression. \[ \frac{3 - \sqrt{5}}{4} \] ### (ii) Rationalizing \( \frac{1}{\sqrt{5} - \sqrt{3}} \) **Step 1:** Multiply by the conjugate \( \sqrt{5} + \sqrt{3} \). \[ \frac{1}{\sqrt{5} - \sqrt{3}} \cdot \frac{\sqrt{5} + \sqrt{3}}{\sqrt{5} + \sqrt{3}} = \frac{\sqrt{5} + \sqrt{3}}{(\sqrt{5})^2 - (\sqrt{3})^2} \] **Step 2:** Simplify the denominator. \[ (\sqrt{5})^2 - (\sqrt{3})^2 = 5 - 3 = 2 \] **Step 3:** Substitute back into the expression. \[ \frac{\sqrt{5} + \sqrt{3}}{2} \] ### (iii) Rationalizing \( \frac{16}{\sqrt{41} + 5} \) **Step 1:** Multiply by the conjugate \( \sqrt{41} - 5 \). \[ \frac{16}{\sqrt{41} + 5} \cdot \frac{\sqrt{41} - 5}{\sqrt{41} - 5} = \frac{16(\sqrt{41} - 5)}{(\sqrt{41})^2 - 5^2} \] **Step 2:** Simplify the denominator. \[ (\sqrt{41})^2 - 5^2 = 41 - 25 = 16 \] **Step 3:** Substitute back into the expression. \[ \frac{16(\sqrt{41} - 5)}{16} = \sqrt{41} - 5 \] ### (iv) Rationalizing \( \frac{30}{5\sqrt{3} + 3\sqrt{5}} \) **Step 1:** Multiply by the conjugate \( 5\sqrt{3} - 3\sqrt{5} \). \[ \frac{30}{5\sqrt{3} + 3\sqrt{5}} \cdot \frac{5\sqrt{3} - 3\sqrt{5}}{5\sqrt{3} - 3\sqrt{5}} = \frac{30(5\sqrt{3} - 3\sqrt{5})}{(5\sqrt{3})^2 - (3\sqrt{5})^2} \] **Step 2:** Simplify the denominator. \[ (5\sqrt{3})^2 - (3\sqrt{5})^2 = 25 \cdot 3 - 9 \cdot 5 = 75 - 45 = 30 \] **Step 3:** Substitute back into the expression. \[ \frac{30(5\sqrt{3} - 3\sqrt{5})}{30} = 5\sqrt{3} - 3\sqrt{5} \] ### (v) Rationalizing \( \frac{3 - 2\sqrt{2}}{3 + 2\sqrt{2}} \) **Step 1:** Multiply by the conjugate \( 3 - 2\sqrt{2} \). \[ \frac{3 - 2\sqrt{2}}{3 + 2\sqrt{2}} \cdot \frac{3 - 2\sqrt{2}}{3 - 2\sqrt{2}} = \frac{(3 - 2\sqrt{2})^2}{(3 + 2\sqrt{2})(3 - 2\sqrt{2})} \] **Step 2:** Simplify the denominator. \[ (3 + 2\sqrt{2})(3 - 2\sqrt{2}) = 3^2 - (2\sqrt{2})^2 = 9 - 8 = 1 \] **Step 3:** Substitute back into the expression. \[ (3 - 2\sqrt{2})^2 = 9 - 12\sqrt{2} + 8 = 17 - 12\sqrt{2} \] ### Final Answers: 1. \( \frac{3 - \sqrt{5}}{4} \) 2. \( \frac{\sqrt{5} + \sqrt{3}}{2} \) 3. \( \sqrt{41} - 5 \) 4. \( 5\sqrt{3} - 3\sqrt{5} \) 5. \( 17 - 12\sqrt{2} \)

Let's rationalize the denominators of the given expressions step by step. ### (i) Rationalizing \( \frac{1}{3 + \sqrt{5}} \) **Step 1:** Multiply the numerator and denominator by the conjugate of the denominator, which is \( 3 - \sqrt{5} \). \[ \frac{1}{3 + \sqrt{5}} \cdot \frac{3 - \sqrt{5}}{3 - \sqrt{5}} = \frac{3 - \sqrt{5}}{(3 + \sqrt{5})(3 - \sqrt{5})} ...
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NAGEEN PRAKASHAN-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 decending 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. sqrt(5+2sqrt(6))+sqrt(8-2sqrt(15))

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  17. If (9^(n)xx3^(2)xx(3^(-n//2))^(-2)-(27)^(n))/(3^(3m)xx2^(3))=(1)/(27),...

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

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