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Evaluate using binomial theorem: (i) (...

Evaluate using binomial theorem:
`(i) (sqrt(2)+1)^(6) +(sqrt(2)-1)^(6)`
`(ii) (sqrt(5)+sqrt(2))^(4)-(sqrt(5)-sqrt(2))^(4)`

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To solve the given problems using the Binomial Theorem, we will follow a systematic approach for each part. ### Part (i): Evaluate \((\sqrt{2}+1)^{6} + (\sqrt{2}-1)^{6}\) 1. **Apply the Binomial Theorem**: The Binomial Theorem states that: \[ (a + b)^n = \sum_{r=0}^{n} \binom{n}{r} a^{n-r} b^r \] For \((\sqrt{2}+1)^{6}\), we have \(a = \sqrt{2}\), \(b = 1\), and \(n = 6\). Expanding \((\sqrt{2}+1)^{6}\): \[ (\sqrt{2}+1)^{6} = \sum_{r=0}^{6} \binom{6}{r} (\sqrt{2})^{6-r} (1)^r \] This gives us: \[ = \binom{6}{0} (\sqrt{2})^{6} + \binom{6}{1} (\sqrt{2})^{5} + \binom{6}{2} (\sqrt{2})^{4} + \binom{6}{3} (\sqrt{2})^{3} + \binom{6}{4} (\sqrt{2})^{2} + \binom{6}{5} (\sqrt{2})^{1} + \binom{6}{6} (1)^{6} \] Simplifying: \[ = \binom{6}{0} \cdot 2^{3} + \binom{6}{1} \cdot 2^{5/2} + \binom{6}{2} \cdot 2^{4} + \binom{6}{3} \cdot 2^{3/2} + \binom{6}{4} \cdot 2 + \binom{6}{5} \cdot \sqrt{2} + \binom{6}{6} \] 2. **Calculate \((\sqrt{2}-1)^{6}\)**: Similarly, for \((\sqrt{2}-1)^{6}\): \[ (\sqrt{2}-1)^{6} = \sum_{r=0}^{6} \binom{6}{r} (\sqrt{2})^{6-r} (-1)^r \] This gives us: \[ = \binom{6}{0} (\sqrt{2})^{6} - \binom{6}{1} (\sqrt{2})^{5} + \binom{6}{2} (\sqrt{2})^{4} - \binom{6}{3} (\sqrt{2})^{3} + \binom{6}{4} (\sqrt{2})^{2} - \binom{6}{5} (\sqrt{2}) + \binom{6}{6} \] 3. **Combine the two expansions**: Now, we add the two expansions: \[ (\sqrt{2}+1)^{6} + (\sqrt{2}-1)^{6} \] Notice that terms with odd powers of \(\sqrt{2}\) will cancel out: \[ = 2\left(\binom{6}{0} \cdot 2^{3} + \binom{6}{2} \cdot 2^{4} + \binom{6}{4} \cdot 2\right) + 2 \] 4. **Calculate the coefficients**: \[ = 2\left(1 \cdot 8 + 15 \cdot 4 + 15 \cdot 2\right) + 2 \] \[ = 2(8 + 60 + 30) + 2 = 2(98) + 2 = 196 + 2 = 198 \] ### Final answer for Part (i): \[ (\sqrt{2}+1)^{6} + (\sqrt{2}-1)^{6} = 198 \] --- ### Part (ii): Evaluate \((\sqrt{5}+\sqrt{2})^{4} - (\sqrt{5}-\sqrt{2})^{4}\) 1. **Apply the Binomial Theorem**: For \((\sqrt{5}+\sqrt{2})^{4}\): \[ (\sqrt{5}+\sqrt{2})^{4} = \sum_{r=0}^{4} \binom{4}{r} (\sqrt{5})^{4-r} (\sqrt{2})^{r} \] This gives us: \[ = \binom{4}{0} (\sqrt{5})^{4} + \binom{4}{1} (\sqrt{5})^{3} (\sqrt{2}) + \binom{4}{2} (\sqrt{5})^{2} (\sqrt{2})^{2} + \binom{4}{3} (\sqrt{5}) (\sqrt{2})^{3} + \binom{4}{4} (\sqrt{2})^{4} \] 2. **Calculate \((\sqrt{5}-\sqrt{2})^{4}\)**: Similarly, for \((\sqrt{5}-\sqrt{2})^{4}\): \[ (\sqrt{5}-\sqrt{2})^{4} = \sum_{r=0}^{4} \binom{4}{r} (\sqrt{5})^{4-r} (-\sqrt{2})^{r} \] 3. **Combine the two expansions**: Now, we subtract the two expansions: \[ (\sqrt{5}+\sqrt{2})^{4} - (\sqrt{5}-\sqrt{2})^{4} \] Notice that terms with even powers of \(\sqrt{2}\) will cancel out: \[ = 2\left(\binom{4}{1} (\sqrt{5})^{3} (\sqrt{2}) + \binom{4}{3} (\sqrt{5}) (\sqrt{2})^{3}\right) \] 4. **Calculate the coefficients**: \[ = 2\left(4 (\sqrt{5})^{3} (\sqrt{2}) + 4 (\sqrt{5}) (\sqrt{2})^{3}\right) \] \[ = 8\left(\sqrt{5}^{3} \sqrt{2} + \sqrt{5} \sqrt{2}^{3}\right) = 8\left(5\sqrt{5}\sqrt{2} + 2\sqrt{5}\sqrt{2}\right) = 8 \cdot 7\sqrt{10} = 56\sqrt{10} \] ### Final answer for Part (ii): \[ (\sqrt{5}+\sqrt{2})^{4} - (\sqrt{5}-\sqrt{2})^{4} = 56\sqrt{10} \] ---

To solve the given problems using the Binomial Theorem, we will follow a systematic approach for each part. ### Part (i): Evaluate \((\sqrt{2}+1)^{6} + (\sqrt{2}-1)^{6}\) 1. **Apply the Binomial Theorem**: The Binomial Theorem states that: \[ (a + b)^n = \sum_{r=0}^{n} \binom{n}{r} a^{n-r} b^r ...
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NAGEEN PRAKASHAN ENGLISH-BINOMIAL THEOREM-Exercise 8A
  1. Find the value of (sqrt(2)+1)^6-(sqrt(2)-1)^6dot

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  2. If x= sqrt5+sqrt3 and y = sqrt5-sqrt3, then x^4 -y^4

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  3. Find the values of the following using binomial theorem: (i) 49^(4)...

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  4. By using binomial theorem find which number is greater (1.2)^(3000) " ...

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  5. Prove that Sigma(r=0)^(n) ""^(n)C(r).3^(r)=4^(n)

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  6. If n is a positive integer then find the number of terms in the expans...

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  7. Find the number of terms in the expansion of (1+3x+3x^(2)+x^(3))^(15)

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  8. If (1+x+x^(2))^(n)=1 +a(1)x+a(2)x^(2)+a(3)x^(3) +……..+a(2n).x^(2...

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  9. Using binomial theorem, prove that 2^(3n)-7n-1 is divisible by 49 , wh...

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  10. Expand using binomial theorem: (i) (1-2x)^(4)

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  11. Evaluate using binomial theorem: (i) (sqrt(2)+1)^(6) +(sqrt(2)-1)^(6...

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  12. Using binomial theorem, expand {(x+y)^5+(x-y)^5}dot and hence find the...

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  13. Expand (x+y)^(4)-(x-y)^(4). Hence find the value of (3+sqrt(5))^(4) -(...

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  14. Find the values of the following using binomial theorem: (i) 49^(4)...

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  15. By using binomial theorem find which number is greater (1.2)^(3000) " ...

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  16. Prove that Sigma(r=1) ""^(n)C(r).3^(r)=4^(n)

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  17. If n is a positive integer then find the number of terms in the expans...

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  18. Find the number of terms in the expansion of (1+3x+3x^(2)+x^(3))^(15)

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  19. If (1-x+x^2)^n=a0+a1x+a2x^2+ .........+a(2n)x^(2n),\ find the value o...

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  20. By using binomial theorem prove that (2^(3n)-7n-1) is divisible by ...

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