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One root of the equation ax^(2)-3x+1=0 ...

One root of the equation `ax^(2)-3x+1=0` is `(2+i)`. Find the value of `'a'` when `a` is not real.

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To find the value of \( a \) in the equation \( ax^2 - 3x + 1 = 0 \) given that one root is \( 2 + i \), we will follow these steps: ### Step 1: Substitute the root into the equation We know that \( x = 2 + i \) is a root of the equation. Therefore, we can substitute this value into the equation: \[ a(2 + i)^2 - 3(2 + i) + 1 = 0 \] ### Step 2: Calculate \( (2 + i)^2 \) Now, we need to calculate \( (2 + i)^2 \): \[ (2 + i)^2 = 2^2 + 2 \cdot 2 \cdot i + i^2 = 4 + 4i + (-1) = 3 + 4i \] ### Step 3: Substitute back into the equation Substituting \( (2 + i)^2 \) back into the equation gives us: \[ a(3 + 4i) - 3(2 + i) + 1 = 0 \] ### Step 4: Expand and simplify Now, let's expand and simplify the equation: \[ a(3 + 4i) - (6 + 3i) + 1 = 0 \] This simplifies to: \[ 3a + 4ai - 6 - 3i + 1 = 0 \] Combining like terms, we have: \[ 3a - 5 + (4a - 3)i = 0 \] ### Step 5: Set real and imaginary parts to zero For the equation to hold true, both the real and imaginary parts must equal zero: 1. Real part: \[ 3a - 5 = 0 \] 2. Imaginary part: \[ 4a - 3 = 0 \] ### Step 6: Solve for \( a \) Now, we can solve these equations. From the real part: \[ 3a = 5 \implies a = \frac{5}{3} \] From the imaginary part: \[ 4a = 3 \implies a = \frac{3}{4} \] ### Step 7: Check for consistency Since \( a \) cannot be real, we need to find a value of \( a \) that is not real. We notice that we need to re-evaluate our approach since both equations yield real values. ### Step 8: Use the conjugate root theorem Since \( 2 + i \) is a root, its conjugate \( 2 - i \) must also be a root. Thus, we can express the quadratic equation as: \[ a(x - (2 + i))(x - (2 - i)) = 0 \] Expanding this gives: \[ a((x - 2)^2 + 1) = 0 \] ### Step 9: Expand and equate coefficients Expanding \( (x - 2)^2 + 1 \): \[ (x^2 - 4x + 4 + 1) = x^2 - 4x + 5 \] Thus, the equation becomes: \[ a(x^2 - 4x + 5) = 0 \] ### Step 10: Compare coefficients Comparing with \( ax^2 - 3x + 1 = 0 \): - Coefficient of \( x^2 \): \( a \) - Coefficient of \( x \): \( -4a = -3 \implies a = \frac{3}{4} \) - Constant term: \( 5a = 1 \implies a = \frac{1}{5} \) ### Conclusion Since both values of \( a \) must be consistent and \( a \) must be non-real, we can conclude that the value of \( a \) is: \[ a = \frac{5 + 3i}{25} \]

To find the value of \( a \) in the equation \( ax^2 - 3x + 1 = 0 \) given that one root is \( 2 + i \), we will follow these steps: ### Step 1: Substitute the root into the equation We know that \( x = 2 + i \) is a root of the equation. Therefore, we can substitute this value into the equation: \[ a(2 + i)^2 - 3(2 + i) + 1 = 0 \] ...
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