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Suppose a(1),a(2),a(3) are in A.P. and b...

Suppose `a_(1),a_(2),a_(3)` are in A.P. and `b_(1),b_(2),b_(3)` are in H.P. and let `/_\=|(a_(1)-b_(1),a_(1)-b_(2),a_(1)-b_(3)),(a_(2)-b_(1),a_(2)-b_(2),a_(2)-b_(3)),(a_(3)-b_(1),a_(3)-b_(2),a_(3)-b_(3))|`
then

A

`/_\ "is independent of "a_(1),a_(2),a_(3),b_(1),b_(2),b_(3)`

B

`a_(1)-/_\,a_(2)-2/_\,a_(3)-3/_\` are in H.P.

C

`b_(1)+/_\,b_(2)+/_\^(2),b^(3)+/_\` are in H.P.

D

none of these

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The correct Answer is:
To solve the problem, we need to analyze the given conditions and the determinant defined by the differences between the terms in the arithmetic progression (A.P.) and harmonic progression (H.P.). ### Step-by-Step Solution: 1. **Understanding A.P. and H.P.**: - Let \( a_1, a_2, a_3 \) be in A.P. This means: \[ a_2 - a_1 = a_3 - a_2 = d \quad \text{(common difference)} \] - Let \( b_1, b_2, b_3 \) be in H.P. This implies that: \[ \frac{1}{b_1}, \frac{1}{b_2}, \frac{1}{b_3} \text{ are in A.P.} \] Therefore, \[ 2 \cdot \frac{1}{b_2} = \frac{1}{b_1} + \frac{1}{b_3} \implies b_1 + b_3 = 2b_2 \] 2. **Setting Up the Determinant**: - The determinant \( \Delta \) is defined as: \[ \Delta = \begin{vmatrix} a_1 - b_1 & a_1 - b_2 & a_1 - b_3 \\ a_2 - b_1 & a_2 - b_2 & a_2 - b_3 \\ a_3 - b_1 & a_3 - b_2 & a_3 - b_3 \end{vmatrix} \] 3. **Substituting Values**: - Substitute \( a_2 = a_1 + d \) and \( a_3 = a_1 + 2d \) into the determinant: \[ \Delta = \begin{vmatrix} a_1 - b_1 & a_1 - b_2 & a_1 - b_3 \\ (a_1 + d) - b_1 & (a_1 + d) - b_2 & (a_1 + d) - b_3 \\ (a_1 + 2d) - b_1 & (a_1 + 2d) - b_2 & (a_1 + 2d) - b_3 \end{vmatrix} \] - Simplifying, we have: \[ \Delta = \begin{vmatrix} a_1 - b_1 & a_1 - b_2 & a_1 - b_3 \\ d & d & d \\ 2d & 2d & 2d \end{vmatrix} \] 4. **Calculating the Determinant**: - Notice that the second and third rows are proportional: - Row 2 is \( d \) times Row 1. - Row 3 is \( 2d \) times Row 1. - Since two rows of the determinant are proportional, the determinant evaluates to zero: \[ \Delta = 0 \] 5. **Conclusion**: - Since \( \Delta = 0 \), it implies that the value of the determinant does not depend on the specific values of \( a_1, a_2, a_3, b_1, b_2, b_3 \). ### Final Result: \[ \Delta < 0 \implies \text{The determinant is independent of } a_1, a_2, a_3, b_1, b_2, b_3. \]

To solve the problem, we need to analyze the given conditions and the determinant defined by the differences between the terms in the arithmetic progression (A.P.) and harmonic progression (H.P.). ### Step-by-Step Solution: 1. **Understanding A.P. and H.P.**: - Let \( a_1, a_2, a_3 \) be in A.P. This means: \[ a_2 - a_1 = a_3 - a_2 = d \quad \text{(common difference)} ...
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Suppose a_(1),a_(2),a_(3) are in A.P. and b_(1),b_(2),b_(3) are in H.P. and let Delta=|(a_(1)-b_(1),a_(1)-b_(2),a_(1)-b_(3)),(a_(2)-b_(1),a_(2)-b_(2),a_(2)-b_(3)),(a_(3)-b_(1),a_(3)-b_(2),a_(3)-b_(3))| then prove that

The determinant |(b_(1)+c_(1),c_(1)+a_(1),a_(1)+b_(1)),(b_(2)+c_(2),c_(2)+a_(2),a_(2)+b_(2)),(b_(3)+c_(3),c_(3)+a_(3),a_(3)+b_(3))|

The value of the determinant Delta = |(1 + a_(1) b_(1),1 + a_(1) b_(2),1 + a_(1) b_(3)),(1 + a_(2) b_(1),1 + a_(2) b_(2),1 + a_(2) b_(3)),(1 + a_(3) b_(1) ,1 + a_(3) b_(2),1 + a_(3) b_(3))| , is

det[[2a_(1)b_(1),a_(1)b_(2)+a_(2)b_(1),a_(1)b_(3)+a_(3)b_(1)a_(1)b_(2)+a_(2)b_(1),2a_(2)b_(2),a_(2)b_(3)+a_(3)b_(2)a_(1)b_(3)+a_(3)b_(1),a_(3)b_(2)+a_(2)b_(3),2a_(3)b_(3)]]=

if quad /_=[[a_(1),b_(1),c_(1)a_(2),b_(2),c_(2)a_(3),b_(3),c_(3)]]

Show that if x_(1),x_(2),x_(3) ne 0 |{:(x_(1) +a_(1)b_(1),,a_(1)b_(2),,a_(1)b_(3)),(a_(2)b_(1),,x_(2)+a_(2)b_(2),,a_(2)b_(3)),(a_(3)b_(1),,a_(3)b_(2),,x_(3)+a_(3)b_(3)):}| =x_(1)x_(2)x_(3) (1+(a_(1)b_(1))/(x_(1))+(a_(2)b_(2))/(x_(2))+(a_(3)b_(3))/(x_(3)))

Let = |(2a_(1)b_(1),a_(1)b_(2)+a_(2)b_(1),a_(1)b_(3)+a_(3)b_(1)),(a_(1)b_(2)+a_(2)b_(1),2a_(2)b_(2),a_(2)b_(3)+a_(3)b_(2)),(a_(1)b_(3)+a_(3)b_(1),a_(3)b_(2)+a_(2)b_(3),2a_(3)b_(3))| Express the determinant D as a product of two determinants. Hence or otherwise show that D = 0.

the value of the determinant |{:((a_(1)-b_(1))^(2),,(a_(1)-b_(2))^(2),,(a_(1)-b_(3))^(2),,(a_(1)-b_(4))^(2)),((a_(2)-b_(1))^(2),,(a_(2)-b_(2))^(2) ,,(a_(2)-b_(3))^(2),,(a_(3)-b_(4))^(2)),((a_(3)-b_(1))^(2),,(a_(3)-b_(2))^(2),,(a_(3)-b_(3))^(2),,(a_(3)-b_(4))^(2)),((a_(4)-b_(1))^(2),,(a_(4)-b_(2))^(2),,(a_(4)-b_(3))^(2),,(a_(4)-b_(4))^(2)):}| is

Show that |[a_(1),b_(1),-c_(1)],[-a_(2),-b_(2),c_(2)],[a_(3),b_(3),-c_(3)]|=|[a_(1),b_(1),c_(1)],[a_(2),b_(2),c_(2)],[a_(3),b_(3),c_(3)]|

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