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Area of triangle whose vertices are (a,a...

Area of triangle whose vertices are `(a,a^2),(b,b^2),(c,c^2)` is `1/2` . and area of another triangle whose vertices are `(p,p^2),(q,q^2) and (r,r^2)` is 4, then the value of `|((1+ap)^2,(1+bp)^2,(1+cp)^2),((1+aq)^2,(1+bp)^2,(1+cq)^2),((1+ar)^2,(1+br)^2,(1+cr)^2)|` is (A) 2 (B) 4 (C) 8 (D) 16

A

`2`

B

`4`

C

`8`

D

`16`

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To solve the problem step by step, we need to find the value of the determinant given the areas of two triangles formed by specific vertices. ### Step 1: Understand the Area of a Triangle The area of a triangle with vertices at \((x_1, y_1)\), \((x_2, y_2)\), and \((x_3, y_3)\) can be calculated using the formula: \[ \text{Area} = \frac{1}{2} \left| \begin{vmatrix} 1 & 1 & 1 \\ x_1 & x_2 & x_3 \\ y_1 & y_2 & y_3 \end{vmatrix} \right| \] ### Step 2: Area of the First Triangle For the first triangle with vertices \((a, a^2)\), \((b, b^2)\), and \((c, c^2)\), we have: \[ \text{Area} = \frac{1}{2} \left| \begin{vmatrix} 1 & 1 & 1 \\ a & b & c \\ a^2 & b^2 & c^2 \end{vmatrix} \right| = \frac{1}{2} \] This implies: \[ \left| \begin{vmatrix} 1 & 1 & 1 \\ a & b & c \\ a^2 & b^2 & c^2 \end{vmatrix} \right| = 1 \] ### Step 3: Area of the Second Triangle For the second triangle with vertices \((p, p^2)\), \((q, q^2)\), and \((r, r^2)\), we have: \[ \text{Area} = \frac{1}{2} \left| \begin{vmatrix} 1 & 1 & 1 \\ p & q & r \\ p^2 & q^2 & r^2 \end{vmatrix} \right| = 4 \] This implies: \[ \left| \begin{vmatrix} 1 & 1 & 1 \\ p & q & r \\ p^2 & q^2 & r^2 \end{vmatrix} \right| = 8 \] ### Step 4: Set Up the Determinant We need to evaluate the determinant: \[ D = \left| \begin{matrix} (1 + ap)^2 & (1 + bp)^2 & (1 + cp)^2 \\ (1 + aq)^2 & (1 + bq)^2 & (1 + cq)^2 \\ (1 + ar)^2 & (1 + br)^2 & (1 + cr)^2 \end{matrix} \right| \] ### Step 5: Expand the Determinant Each term in the determinant can be rewritten using the identity \((x + y)^2 = x^2 + 2xy + y^2\): \[ D = \left| \begin{matrix} 1 + 2ap + a^2p^2 & 1 + 2bp + b^2p^2 & 1 + 2cp + c^2p^2 \\ 1 + 2aq + a^2q^2 & 1 + 2bq + b^2q^2 & 1 + 2cq + c^2q^2 \\ 1 + 2ar + a^2r^2 & 1 + 2br + b^2r^2 & 1 + 2cr + c^2r^2 \end{matrix} \right| \] ### Step 6: Factor Out Common Terms We can factor out 2 from each of the first rows: \[ D = 2^3 \left| \begin{matrix} 1 & 1 & 1 \\ a & b & c \\ a^2 & b^2 & c^2 \end{matrix} \right| \left| \begin{matrix} 1 & 1 & 1 \\ p & q & r \\ p^2 & q^2 & r^2 \end{matrix} \right| \] This gives us: \[ D = 8 \cdot 1 \cdot 8 = 64 \] ### Step 7: Final Calculation Since we factored out \(2^3\) (which is 8), we have: \[ D = 8 \cdot 8 = 64 \] ### Conclusion The value of the determinant is \(16\).

To solve the problem step by step, we need to find the value of the determinant given the areas of two triangles formed by specific vertices. ### Step 1: Understand the Area of a Triangle The area of a triangle with vertices at \((x_1, y_1)\), \((x_2, y_2)\), and \((x_3, y_3)\) can be calculated using the formula: \[ \text{Area} = \frac{1}{2} \left| \begin{vmatrix} 1 & 1 & 1 \\ x_1 & x_2 & x_3 \\ ...
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