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If the area of the triangle formed by th...

If the area of the triangle formed by the points `(2a,b), (a+b, 2b+a)` and (2b, 2a) be `Delta_(1)` and the area of the triangle whose vertices are `(a+b, a-b), (3b-a, b+3a)` and `(3a-b, 3b-a)` be `Delta_(2)`, then the value of `Delta_(2)//Delta_(1)` is

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To find the value of \(\frac{\Delta_2}{\Delta_1}\), we will first calculate the areas \(\Delta_1\) and \(\Delta_2\) using the formula for the area of a triangle given its vertices. ### Step 1: Calculate \(\Delta_1\) The vertices of the first triangle are given as: - \(A(2a, b)\) - \(B(a+b, 2b+a)\) - \(C(2b, 2a)\) Using the formula for the area of a triangle with vertices \((x_1, y_1)\), \((x_2, y_2)\), \((x_3, y_3)\): \[ \text{Area} = \frac{1}{2} \left| x_1(y_2 - y_3) + x_2(y_3 - y_1) + x_3(y_1 - y_2) \right| \] Substituting the coordinates: \[ \Delta_1 = \frac{1}{2} \left| 2a((2b + a) - 2a) + (a + b)(2a - b) + 2b(b - (2b + a)) \right| \] Calculating each term: 1. \(2a((2b + a) - 2a) = 2a(2b - a) = 4ab - 2a^2\) 2. \((a + b)(2a - b) = 2a^2 + 2ab - ab - b^2 = 2a^2 + ab - b^2\) 3. \(2b(b - (2b + a)) = 2b(b - 2b - a) = 2b(-b - a) = -2b^2 - 2ab\) Combining these: \[ \Delta_1 = \frac{1}{2} \left| (4ab - 2a^2) + (2a^2 + ab - b^2) + (-2b^2 - 2ab) \right| \] \[ = \frac{1}{2} \left| 4ab - 2ab - 2b^2 - b^2 \right| \] \[ = \frac{1}{2} \left| 2ab - 3b^2 \right| \] Thus, we have: \[ \Delta_1 = \frac{1}{2} |2ab - 3b^2| \] ### Step 2: Calculate \(\Delta_2\) The vertices of the second triangle are given as: - \(D(a+b, a-b)\) - \(E(3b-a, b+3a)\) - \(F(3a-b, 3b-a)\) Using the same area formula: \[ \Delta_2 = \frac{1}{2} \left| (a+b)((b+3a) - (3b-a)) + (3b-a)((3b-a) - (a-b)) + (3a-b)((a-b) - (b+3a)) \right| \] Calculating each term: 1. \((a+b)((b+3a) - (3b-a)) = (a+b)(4a - 2b)\) 2. \((3b-a)((3b-a) - (a-b)) = (3b-a)(4b - 2a)\) 3. \((3a-b)((a-b) - (b+3a)) = (3a-b)(-2b - 2a)\) Calculating these terms separately: 1. \((a+b)(4a - 2b) = 4a^2 + 4ab - 2b^2 - 2ab = 4a^2 + 2ab - 2b^2\) 2. \((3b-a)(4b - 2a) = 12b^2 - 6ab - 4ab + 2a^2 = 12b^2 - 10ab + 2a^2\) 3. \((3a-b)(-2b - 2a) = -6ab - 6a^2 + 2b^2\) Combining these: \[ \Delta_2 = \frac{1}{2} \left| (4a^2 + 2ab - 2b^2) + (12b^2 - 10ab + 2a^2) + (-6ab - 6a^2 + 2b^2) \right| \] \[ = \frac{1}{2} \left| 4a^2 + 2a^2 - 6a^2 + 2ab - 10ab - 6ab + 12b^2 - 2b^2 \right| \] \[ = \frac{1}{2} \left| 0a^2 - 14ab + 10b^2 \right| \] Thus, we have: \[ \Delta_2 = \frac{1}{2} |10b^2 - 14ab| \] ### Step 3: Calculate \(\frac{\Delta_2}{\Delta_1}\) Now we can find the ratio: \[ \frac{\Delta_2}{\Delta_1} = \frac{\frac{1}{2} |10b^2 - 14ab|}{\frac{1}{2} |2ab - 3b^2|} = \frac{|10b^2 - 14ab|}{|2ab - 3b^2|} \] ### Final Result: The value of \(\frac{\Delta_2}{\Delta_1}\) is: \[ \frac{\Delta_2}{\Delta_1} = \frac{|10b^2 - 14ab|}{|2ab - 3b^2|} \]
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