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In in the expansion of (1+px)^(q), q bel...

In in the expansion of `(1+px)^(q)`, `q` belongs to `N`, the coefficients of `x` and `x^(2)` are `12` and `60` respectively then `p` and `q` are

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To solve the problem, we need to find the values of \( p \) and \( q \) in the expansion of \( (1 + px)^q \) given that the coefficients of \( x \) and \( x^2 \) are 12 and 60, respectively. ### Step-by-Step Solution: 1. **Identify the Coefficients**: The coefficient of \( x^r \) in the expansion of \( (1 + px)^q \) is given by the formula: \[ C(r) = \binom{q}{r} p^r \] For \( r = 1 \) (coefficient of \( x \)): \[ C(1) = \binom{q}{1} p = qp \] For \( r = 2 \) (coefficient of \( x^2 \)): \[ C(2) = \binom{q}{2} p^2 = \frac{q(q-1)}{2} p^2 \] 2. **Set Up the Equations**: From the problem, we know: \[ qp = 12 \quad \text{(1)} \] \[ \frac{q(q-1)}{2} p^2 = 60 \quad \text{(2)} \] 3. **Substitute Equation (1) into Equation (2)**: From equation (1), we can express \( p \) in terms of \( q \): \[ p = \frac{12}{q} \] Substitute \( p \) into equation (2): \[ \frac{q(q-1)}{2} \left(\frac{12}{q}\right)^2 = 60 \] Simplifying this gives: \[ \frac{q(q-1)}{2} \cdot \frac{144}{q^2} = 60 \] \[ \frac{72(q-1)}{q} = 60 \] 4. **Cross Multiply and Simplify**: Cross-multiplying gives: \[ 72(q - 1) = 60q \] Expanding this: \[ 72q - 72 = 60q \] Rearranging terms: \[ 72q - 60q = 72 \] \[ 12q = 72 \] \[ q = 6 \] 5. **Find \( p \)**: Substitute \( q = 6 \) back into equation (1): \[ 6p = 12 \implies p = \frac{12}{6} = 2 \] ### Final Answer: Thus, the values of \( p \) and \( q \) are: \[ p = 2, \quad q = 6 \]
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AAKASH INSTITUTE ENGLISH-BINOMIAL THEOREM-Assignment (section-A)
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  3. In in the expansion of (1+px)^(q), q belongs to N, the coefficients of...

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  4. The expansion of (x^(alpha)+1/x^(beta))^(n) has constant term, if

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  5. The number of rational terms in the expansion of ((25)^(1/3) + 1/(25)^...

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  6. The number of zeros at the end of (101)^(11)-1 is

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  7. In the expantion of (1+kx)^(4) the cofficient of x^(3) is 32, then th...

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  8. In the expansion of (3+x/2)^(n) the coefficients of x^(7) and x^(8) ar...

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  9. sqrt(5){(sqrt(5)+1)^(50)-(sqrt(5)-1)^(50)}

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  10. In expansion of (x+a)^(5), T(2):T(3)=1:3, then x:a is equal to

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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. The middle term in the expansioin of (1+x)^(2n) is

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  13. Cofficient of x^(12) in the expansion of (1+x^(2))^50(x+1/x)^(-10)

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  14. The number of terms in expansion of (x^(2)+18x+81)^(15) is

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  15. The term independent of x in the expanion of (root(6)(x)-(2)/(root(3)(...

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  16. The middle terms in the expansion of (1+x)^(2n+1) is (are)

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  17. (1.003)^(4) is nearby equal to

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  18. The nubmber of non - zeroes terns in the expansion of (1+sqrt(5))^(6)+...

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  19. The number of non -zeroes terms in the expansion of (sqrt(7)+1)^(75)-(...

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  20. The number of terms in the expansion if (a+b+c)^(12) is

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