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Find the constant term in the expansion of `(2x^(4)-(1)/(3x^(7)))^(11)`

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To find the constant term in the expansion of \((2x^{4} - \frac{1}{3x^{7}})^{11}\), we will follow these steps: ### Step 1: Identify the General Term The general term \(T_{r+1}\) in the binomial expansion of \((a + b)^n\) is given by: \[ T_{r+1} = \binom{n}{r} a^{n-r} b^r \] In our case, \(a = 2x^{4}\), \(b = -\frac{1}{3x^{7}}\), and \(n = 11\). Therefore, the general term can be written as: \[ T_{r+1} = \binom{11}{r} (2x^{4})^{11-r} \left(-\frac{1}{3x^{7}}\right)^{r} \] ### Step 2: Simplify the General Term Now, we simplify \(T_{r+1}\): \[ T_{r+1} = \binom{11}{r} (2^{11-r} (x^{4})^{11-r}) \left(-\frac{1}{3}\right)^{r} (x^{-7})^{r} \] This simplifies to: \[ T_{r+1} = \binom{11}{r} 2^{11-r} (-1)^{r} \frac{1}{3^{r}} x^{4(11-r) - 7r} \] \[ = \binom{11}{r} 2^{11-r} (-1)^{r} \frac{1}{3^{r}} x^{44 - 4r - 7r} \] \[ = \binom{11}{r} 2^{11-r} (-1)^{r} \frac{1}{3^{r}} x^{44 - 11r} \] ### Step 3: Find the Constant Term The constant term is the term where the exponent of \(x\) is zero: \[ 44 - 11r = 0 \] Solving for \(r\): \[ 44 = 11r \implies r = 4 \] ### Step 4: Substitute \(r\) into the General Term Now, we substitute \(r = 4\) back into the general term: \[ T_{5} = \binom{11}{4} 2^{11-4} (-1)^{4} \frac{1}{3^{4}} \] Calculating each part: \[ = \binom{11}{4} 2^{7} \cdot 1 \cdot \frac{1}{81} \] \[ = \binom{11}{4} \cdot 128 \cdot \frac{1}{81} \] ### Step 5: Calculate \(\binom{11}{4}\) \[ \binom{11}{4} = \frac{11!}{4!(11-4)!} = \frac{11 \times 10 \times 9 \times 8}{4 \times 3 \times 2 \times 1} = 330 \] ### Step 6: Final Calculation Now we can calculate the constant term: \[ \text{Constant Term} = 330 \cdot 128 \cdot \frac{1}{81} \] Calculating \(330 \cdot 128\): \[ 330 \cdot 128 = 42240 \] Now divide by \(81\): \[ \text{Constant Term} = \frac{42240}{81} = 520 \] ### Final Answer The constant term in the expansion is \(520\).

To find the constant term in the expansion of \((2x^{4} - \frac{1}{3x^{7}})^{11}\), we will follow these steps: ### Step 1: Identify the General Term The general term \(T_{r+1}\) in the binomial expansion of \((a + b)^n\) is given by: \[ T_{r+1} = \binom{n}{r} a^{n-r} b^r \] In our case, \(a = 2x^{4}\), \(b = -\frac{1}{3x^{7}}\), and \(n = 11\). Therefore, the general term can be written as: ...
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NAGEEN PRAKASHAN ENGLISH-BINOMIAL THEOREM-Miscellaneous Exericse
  1. Find the constant term in the expansion of (2x^(4)-(1)/(3x^(7)))^(11)

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  2. Find a, b and n in the expansion of (a+b)^nif the first three terms ...

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  3. If the coefficients of x^2a n d\ x^3 in the expansion o (3+a x)^9 are ...

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  4. Find the coefficient of a^4 in the product (1+a)^4(2-a)^5 using binomi...

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  5. If a and b are distinct integers, prove that a - b is a factor of a^n-...

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  6. Evaluate (sqrt(3)+sqrt(2))^6-(sqrt(3)-sqrt(2))^6dot

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  7. Find the value of (a^2+sqrt(a^2-1))^4+(a^2-sqrt(a^2-1))^4.

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  8. Find an approximation of (0. 99)^5 using the first three terms of its ...

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  9. Find n, if the ratio of the fifth term from the beginning to the fi...

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  10. Using binomial theorem expand (1+x/2-2/x)^4,\ x!=0.

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  11. Find the expansion of (3x^2-2a x+3a^2)^3 using binomial theorem.

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  12. Find a, b and n in the expansion of (a+b)^nif the first three terms ...

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  13. If the coefficients of x^2a n d\ x^3 in the expansion o (3+a x)^9 are ...

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  14. Find the coefficient of x^5 in the expansion of (1 + 2x)^6 (1-x)^7.

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  15. If a and b are distinct integers, prove that a - b is a factor of a^n-...

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  16. Evaluate (sqrt(3)+sqrt(2))^6-(sqrt(3)-sqrt(2))^6dot

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  17. Find the value of (a^2+sqrt(a^2-1))^4+(a^2-sqrt(a^2-1))^4.

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  18. Find an approximation of (0. 99)^5using the first three terms of its ...

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  19. Find n, if the ratio of the fifth term from the beginning to the fi...

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  20. Expand using Binomial Theorem (1+x/2-2/x)^4,x!=0.

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  21. Find the expansion of (3x^2-2a x+3a^2)^3 using binomial theorem.

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