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If x=2+sqrt(3), then find the value of x...

If `x=2+sqrt(3)`, then find the value of `x^(4)-4x^(3)+x^(2)+x+1`.

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To solve the problem where \( x = 2 + \sqrt{3} \) and we need to find the value of \( x^4 - 4x^3 + x^2 + x + 1 \), we will follow these steps: ### Step 1: Calculate \( x^2 \) We start by calculating \( x^2 \): \[ x^2 = (2 + \sqrt{3})^2 = 2^2 + 2 \cdot 2 \cdot \sqrt{3} + (\sqrt{3})^2 \] \[ = 4 + 4\sqrt{3} + 3 = 7 + 4\sqrt{3} \] ### Step 2: Calculate \( x^3 \) Next, we calculate \( x^3 \) using \( x^2 \): \[ x^3 = x^2 \cdot x = (7 + 4\sqrt{3})(2 + \sqrt{3}) \] Using the distributive property: \[ = 7 \cdot 2 + 7 \cdot \sqrt{3} + 4\sqrt{3} \cdot 2 + 4\sqrt{3} \cdot \sqrt{3} \] \[ = 14 + 7\sqrt{3} + 8\sqrt{3} + 12 = 26 + 15\sqrt{3} \] ### Step 3: Calculate \( x^4 \) Now, we calculate \( x^4 \) using \( x^2 \): \[ x^4 = (x^2)^2 = (7 + 4\sqrt{3})^2 \] \[ = 7^2 + 2 \cdot 7 \cdot 4\sqrt{3} + (4\sqrt{3})^2 \] \[ = 49 + 56\sqrt{3} + 48 = 97 + 56\sqrt{3} \] ### Step 4: Substitute into the expression Now we substitute \( x^4 \), \( x^3 \), \( x^2 \), and \( x \) into the expression \( x^4 - 4x^3 + x^2 + x + 1 \): \[ x^4 - 4x^3 + x^2 + x + 1 = (97 + 56\sqrt{3}) - 4(26 + 15\sqrt{3}) + (7 + 4\sqrt{3}) + (2 + \sqrt{3}) + 1 \] ### Step 5: Simplify the expression Calculating \( -4x^3 \): \[ -4(26 + 15\sqrt{3}) = -104 - 60\sqrt{3} \] Now substituting everything back: \[ = (97 + 56\sqrt{3}) - (104 + 60\sqrt{3}) + (7 + 4\sqrt{3}) + (2 + \sqrt{3}) + 1 \] Combining like terms: \[ = (97 - 104 + 7 + 2 + 1) + (56\sqrt{3} - 60\sqrt{3} + 4\sqrt{3} + \sqrt{3}) \] Calculating the constants: \[ = (97 - 104 + 7 + 2 + 1) = 3 \] Calculating the square root terms: \[ = (56 - 60 + 4 + 1)\sqrt{3} = 1\sqrt{3} = \sqrt{3} \] Thus, the final result is: \[ = 3 + \sqrt{3} \] ### Final Answer The value of \( x^4 - 4x^3 + x^2 + x + 1 \) is \( 3 + \sqrt{3} \).

To solve the problem where \( x = 2 + \sqrt{3} \) and we need to find the value of \( x^4 - 4x^3 + x^2 + x + 1 \), we will follow these steps: ### Step 1: Calculate \( x^2 \) We start by calculating \( x^2 \): \[ x^2 = (2 + \sqrt{3})^2 = 2^2 + 2 \cdot 2 \cdot \sqrt{3} + (\sqrt{3})^2 \] \[ ...
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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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