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Find the values of a and b in each of th...

Find the values of a and b in each of the
`(sqrt(7)-2)/(sqrt(7)+2)= a sqrt(7)+b`

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To find the values of \( a \) and \( b \) in the equation \[ \frac{\sqrt{7}-2}{\sqrt{7}+2} = a\sqrt{7} + b, \] we will follow these steps: ### Step 1: Multiply by the Conjugate To simplify the left-hand side, we will multiply both the numerator and denominator by the conjugate of the denominator, which is \( \sqrt{7} - 2 \): \[ \frac{(\sqrt{7}-2)(\sqrt{7}-2)}{(\sqrt{7}+2)(\sqrt{7}-2)}. \] ### Step 2: Expand the Numerator and Denominator Now, we will expand both the numerator and the denominator: - **Numerator**: \[ (\sqrt{7}-2)(\sqrt{7}-2) = (\sqrt{7})^2 - 2 \cdot \sqrt{7} \cdot 2 + 2^2 = 7 - 4\sqrt{7} + 4 = 11 - 4\sqrt{7}. \] - **Denominator**: \[ (\sqrt{7}+2)(\sqrt{7}-2) = (\sqrt{7})^2 - (2)^2 = 7 - 4 = 3. \] So, we have: \[ \frac{11 - 4\sqrt{7}}{3}. \] ### Step 3: Simplify the Expression Now we can simplify the expression: \[ \frac{11}{3} - \frac{4\sqrt{7}}{3}. \] This can be rewritten as: \[ -\frac{4}{3}\sqrt{7} + \frac{11}{3}. \] ### Step 4: Compare with the Right Side Now we compare this with the right side of the equation \( a\sqrt{7} + b \): \[ -\frac{4}{3}\sqrt{7} + \frac{11}{3} = a\sqrt{7} + b. \] From this comparison, we can identify: - The coefficient of \( \sqrt{7} \): \( a = -\frac{4}{3} \) - The constant term: \( b = \frac{11}{3} \) ### Final Values Thus, the values of \( a \) and \( b \) are: \[ a = -\frac{4}{3}, \quad b = \frac{11}{3}. \] ---
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ICSE-RATIONAL AND IRRATIONAL NUMBERS -EXERCISE 1 (C)
  1. Rationalize the denominatiors of : (2sqrt(5)+3sqrt(2))/(2sqrt(5)-3s...

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  2. Find the values of a and b in each of the (2+sqrt(3))/(2-sqrt(3))= ...

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  3. Find the values of a and b in each of the (sqrt(7)-2)/(sqrt(7)+2)= ...

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  4. Find the values of a and b in each of the (3)/(sqrt(3)-sqrt(2))= a...

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  5. Find the values of a and b in each of the (5+3sqrt(2))/(5-3sqrt(2)...

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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