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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: Write the general term in the binomial expansion The general term (the \( r+1 \)th term) in the expansion of \( (a + b)^n \) is given by: \[ T_{r+1} = \binom{n}{r} a^{n-r} b^r \] For our expression, let \( a = 2x^4 \) and \( b = -\frac{1}{3x^7} \), and \( n = 11 \). Therefore, the \( r+1 \)th term is: \[ T_{r+1} = \binom{11}{r} (2x^4)^{11-r} \left(-\frac{1}{3x^7}\right)^r \] ### Step 2: Simplify the general term Now, we simplify this term: \[ T_{r+1} = \binom{11}{r} (2^{11-r} (x^4)^{11-r}) \left(-\frac{1}{3^r (x^7)^r}\right) \] This can be rewritten as: \[ T_{r+1} = \binom{11}{r} (-1)^r \frac{2^{11-r}}{3^r} x^{4(11-r) - 7r} \] Simplifying the exponent of \( x \): \[ T_{r+1} = \binom{11}{r} (-1)^r \frac{2^{11-r}}{3^r} x^{44 - 4r - 7r} = \binom{11}{r} (-1)^r \frac{2^{11-r}}{3^r} x^{44 - 11r} \] ### Step 3: Find the constant term For the term to be constant, the exponent of \( x \) must be zero: \[ 44 - 11r = 0 \] Solving for \( r \): \[ 11r = 44 \implies r = 4 \] ### Step 4: Substitute \( r \) back to find the constant term Now, substitute \( r = 4 \) into the general term: \[ T_{5} = \binom{11}{4} (-1)^4 \frac{2^{11-4}}{3^4} \] Calculating this: \[ T_{5} = \binom{11}{4} \frac{2^7}{3^4} \] Calculating \( \binom{11}{4} \): \[ \binom{11}{4} = \frac{11 \times 10 \times 9 \times 8}{4 \times 3 \times 2 \times 1} = 330 \] Now substituting this value: \[ T_{5} = 330 \cdot \frac{128}{81} = \frac{42240}{81} \] ### Final Answer Thus, the constant term in the expansion of \( (2x^4 - \frac{1}{3x^7})^{11} \) is: \[ \frac{42240}{81} \]

To find the constant term in the expansion of \( (2x^4 - \frac{1}{3x^7})^{11} \), we will follow these steps: ### Step 1: Write the general term in the binomial expansion The general term (the \( r+1 \)th term) in the expansion of \( (a + b)^n \) is given by: \[ T_{r+1} = \binom{n}{r} a^{n-r} b^r \] For our expression, let \( a = 2x^4 \) and \( b = -\frac{1}{3x^7} \), and \( n = 11 \). Therefore, the \( r+1 \)th term is: ...
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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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