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Find the term independent of x (constant...

Find the term independent of x (constant term) in the following expansion:
`(i) (x^(2)-(1)/(3x))^(9) " "(ii) (x-(1)/(x))^(10)`

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To find the term independent of \( x \) (constant term) in the given expansions, we will use the Binomial Theorem. Let's solve each part step by step. ### Part (i): \( (x^2 - \frac{1}{3x})^9 \) 1. **Identify the General Term**: The general term \( T_{r+1} \) in the expansion of \( (a + b)^n \) is given by: \[ T_{r+1} = \binom{n}{r} a^{n-r} b^r \] Here, \( a = x^2 \), \( b = -\frac{1}{3x} \), and \( n = 9 \). Thus, the general term becomes: \[ T_{r+1} = \binom{9}{r} (x^2)^{9-r} \left(-\frac{1}{3x}\right)^r \] 2. **Simplify the General Term**: \[ T_{r+1} = \binom{9}{r} (x^{2(9-r)}) \left(-\frac{1}{3}\right)^r (x^{-r}) \] \[ = \binom{9}{r} (-1)^r \frac{1}{3^r} x^{18 - 3r} \] 3. **Find the Term Independent of \( x \)**: We want the exponent of \( x \) to be zero: \[ 18 - 3r = 0 \] Solving for \( r \): \[ 3r = 18 \implies r = 6 \] 4. **Substitute \( r \) Back into the General Term**: Now, substitute \( r = 6 \) into the general term: \[ T_{7} = \binom{9}{6} (-1)^6 \frac{1}{3^6} x^{18 - 18} = \binom{9}{6} \frac{1}{729} \] 5. **Calculate \( \binom{9}{6} \)**: \[ \binom{9}{6} = \binom{9}{3} = \frac{9 \times 8 \times 7}{3 \times 2 \times 1} = 84 \] Therefore, the constant term is: \[ T_{7} = 84 \times \frac{1}{729} = \frac{84}{729} = \frac{28}{243} \] ### Part (ii): \( (x - \frac{1}{x})^{10} \) 1. **Identify the General Term**: The general term \( T_{r+1} \) in this case is: \[ T_{r+1} = \binom{10}{r} x^{10-r} \left(-\frac{1}{x}\right)^r \] 2. **Simplify the General Term**: \[ T_{r+1} = \binom{10}{r} x^{10-r} (-1)^r x^{-r} = \binom{10}{r} (-1)^r x^{10 - 2r} \] 3. **Find the Term Independent of \( x \)**: Set the exponent of \( x \) to zero: \[ 10 - 2r = 0 \] Solving for \( r \): \[ 2r = 10 \implies r = 5 \] 4. **Substitute \( r \) Back into the General Term**: Substitute \( r = 5 \): \[ T_{6} = \binom{10}{5} (-1)^5 x^{10 - 10} = \binom{10}{5} (-1) \] 5. **Calculate \( \binom{10}{5} \)**: \[ \binom{10}{5} = \frac{10 \times 9 \times 8 \times 7 \times 6}{5 \times 4 \times 3 \times 2 \times 1} = 252 \] Therefore, the constant term is: \[ T_{6} = -252 \] ### Final Answers: - For part (i): The term independent of \( x \) is \( \frac{28}{243} \). - For part (ii): The term independent of \( x \) is \( -252 \).

To find the term independent of \( x \) (constant term) in the given expansions, we will use the Binomial Theorem. Let's solve each part step by step. ### Part (i): \( (x^2 - \frac{1}{3x})^9 \) 1. **Identify the General Term**: The general term \( T_{r+1} \) in the expansion of \( (a + b)^n \) is given by: \[ T_{r+1} = \binom{n}{r} a^{n-r} b^r ...
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NAGEEN PRAKASHAN ENGLISH-BINOMIAL THEOREM-Exercise 8C
  1. Find the coefficient of x^(40) in the expansion of (1+2x+x^2)^(27)dot

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  2. If 'n' is a positive integer then prove that the coefficient fox^(m) i...

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  3. Find the term independent of x (constant term) in the following expans...

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  4. Prove that the term independent of x in the expansin of (x+1/x)^(2n)i ...

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  5. Find the coefficient of a^5b^7in(a-2b)^(12)

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  6. Find the coefficient of x^(2).y^(7) in the expansion of (x+2y)^(9)

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  7. Prove that the ratio of the coefficient of x^10 in (1 - x^2)^10 & the ...

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  8. Prove that he coefficient of x^n in the expansion of (1+x)^(2n) is twi...

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  9. Find a positive value of m for which the coefficient of x^2 in the ex...

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  10. The sum of the coefficients of x^(32) and x^(-17) in (x^4- 1/(x^3))^15...

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  11. If the coefficient of x^(7)in [ax^(2) + (1/bx)]^(11) equals the coeffi...

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  12. about to only mathematics

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  13. Find the coefficient of x^(10) in the expansion of (1-x^(2))^(10)

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  14. about to only mathematics

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  15. Find the coefficient of x^(40) in the expansion of (1+2x+x^2)^(27)dot

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  16. If 'n' is a positive integer then prove that the coefficient fox^(m) i...

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  17. Find the term independent of x in ((3x^(2))/(2)-(1)/(3x))^(9)

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  18. Prove that the term independent of x in the expansin of (x+1/x)^(2n)i ...

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  19. Find the coefficient of a^5b^7in(a-2b)^(12)

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  20. Find the coefficient of x^(2).y^(7) in the expansion of (x+2y)^(9)

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