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In a triangle A B C ,/C=pi/2dot If tan(A...

In a triangle `A B C ,/_C=pi/2dot` If `tan(A/2)a n dtan(B/2)` are the roots of the equation `a x^2+b x+c=0,(a!=0),` then the value of `(a+b)/c` (where `a , b , c ,` are sides of `` opposite to angles `A , B , C ,` respectively) is

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To solve the problem, we will follow the steps outlined in the video transcript and derive the required value step by step. ### Step 1: Understanding the Triangle and Roots Given a triangle \( ABC \) where \( \angle C = \frac{\pi}{2} \) (90 degrees), we know that: - The roots of the equation \( ax^2 + bx + c = 0 \) are \( \tan\left(\frac{A}{2}\right) \) and \( \tan\left(\frac{B}{2}\right) \). ### Step 2: Using the Properties of Roots From the properties of quadratic equations, if \( \alpha \) and \( \beta \) are the roots, then: - \( \alpha + \beta = -\frac{b}{a} \) - \( \alpha \beta = \frac{c}{a} \) Substituting the roots: - \( \tan\left(\frac{A}{2}\right) + \tan\left(\frac{B}{2}\right) = -\frac{b}{a} \) (1) - \( \tan\left(\frac{A}{2}\right) \tan\left(\frac{B}{2}\right) = \frac{c}{a} \) (2) ### Step 3: Using the Angle Sum Property Since \( \angle A + \angle B + \angle C = \pi \) and \( \angle C = \frac{\pi}{2} \), we have: \[ \angle A + \angle B = \frac{\pi}{2} \] Thus, \[ \frac{A + B}{2} = \frac{\pi}{4} \] ### Step 4: Finding the Tangent Taking the tangent of both sides: \[ \tan\left(\frac{A + B}{2}\right) = \tan\left(\frac{\pi}{4}\right) = 1 \] Using the tangent addition formula: \[ \tan\left(\frac{A}{2} + \frac{B}{2}\right) = \frac{\tan\left(\frac{A}{2}\right) + \tan\left(\frac{B}{2}\right)}{1 - \tan\left(\frac{A}{2}\right)\tan\left(\frac{B}{2}\right)} = 1 \] ### Step 5: Setting Up the Equation From the tangent addition formula, we can equate: \[ \frac{\tan\left(\frac{A}{2}\right) + \tan\left(\frac{B}{2}\right)}{1 - \tan\left(\frac{A}{2}\right)\tan\left(\frac{B}{2}\right)} = 1 \] Cross-multiplying gives: \[ \tan\left(\frac{A}{2}\right) + \tan\left(\frac{B}{2}\right) = 1 - \tan\left(\frac{A}{2}\right)\tan\left(\frac{B}{2}\right) \] ### Step 6: Substituting Values Substituting equations (1) and (2) into the equation we derived: \[ -\frac{b}{a} = 1 - \frac{c}{a} \] Rearranging gives: \[ -\frac{b}{a} + \frac{c}{a} = 1 \] Multiplying through by \( a \): \[ -c + b = a \] Thus, \[ a + b = c \] ### Step 7: Finding the Required Value We need to find the value of: \[ \frac{a + b}{c} \] Substituting \( a + b = c \): \[ \frac{c}{c} = 1 \] ### Final Answer The value of \( \frac{a + b}{c} \) is \( \boxed{1} \). ---

To solve the problem, we will follow the steps outlined in the video transcript and derive the required value step by step. ### Step 1: Understanding the Triangle and Roots Given a triangle \( ABC \) where \( \angle C = \frac{\pi}{2} \) (90 degrees), we know that: - The roots of the equation \( ax^2 + bx + c = 0 \) are \( \tan\left(\frac{A}{2}\right) \) and \( \tan\left(\frac{B}{2}\right) \). ### Step 2: Using the Properties of Roots From the properties of quadratic equations, if \( \alpha \) and \( \beta \) are the roots, then: ...
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