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In a triangle ABC, if (cosA)/a=(cosB)/b=...

In a triangle ABC, if `(cosA)/a=(cosB)/b=(cosC)/c` and the side `a =2`, then area of triangle is

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To solve the problem, we need to find the area of triangle ABC given that \(\frac{\cos A}{a} = \frac{\cos B}{b} = \frac{\cos C}{c}\) and that side \(a = 2\). ### Step 1: Understand the given condition We are given that: \[ \frac{\cos A}{a} = \frac{\cos B}{b} = \frac{\cos C}{c} \] This implies that the ratios of the cosines of the angles to their respective opposite sides are equal. ### Step 2: Use the relationship between angles and sides From the given condition, we can express this as: \[ \frac{\cos A}{a} = k, \quad \frac{\cos B}{b} = k, \quad \frac{\cos C}{c} = k \] where \(k\) is some constant. Rearranging gives us: \[ \cos A = ka, \quad \cos B = kb, \quad \cos C = kc \] ### Step 3: Substitute the value of side \(a\) Since we know \(a = 2\), we can write: \[ \cos A = 2k \] ### Step 4: Apply the Law of Cosines Using the Law of Cosines, we have: \[ c^2 = a^2 + b^2 - 2ab \cos C \] Substituting \(a = 2\) into the equation, we can express the other angles in terms of \(k\) and the sides. ### Step 5: Establish the equality of angles Given that \(\frac{\cos A}{a} = \frac{\cos B}{b} = \frac{\cos C}{c}\), we can derive that: \[ \tan A = \tan B = \tan C \] This implies that: \[ A = B = C \] Thus, triangle ABC is an equilateral triangle. ### Step 6: Calculate the area of the equilateral triangle The area \(A\) of an equilateral triangle with side length \(a\) is given by: \[ \text{Area} = \frac{\sqrt{3}}{4} a^2 \] Substituting \(a = 2\): \[ \text{Area} = \frac{\sqrt{3}}{4} \times (2^2) = \frac{\sqrt{3}}{4} \times 4 = \sqrt{3} \] ### Final Answer The area of triangle ABC is \(\sqrt{3}\). ---

To solve the problem, we need to find the area of triangle ABC given that \(\frac{\cos A}{a} = \frac{\cos B}{b} = \frac{\cos C}{c}\) and that side \(a = 2\). ### Step 1: Understand the given condition We are given that: \[ \frac{\cos A}{a} = \frac{\cos B}{b} = \frac{\cos C}{c} \] This implies that the ratios of the cosines of the angles to their respective opposite sides are equal. ...
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