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If one of the roots of the an equation, ...

If one of the roots of the an equation, `x^(2) - 2x + c =0` is thrice the other, then `c =?`

A

`1/2`

B

`4/3`

C

`-1/2`

D

`3/4`

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The correct Answer is:
To find the value of \( c \) in the equation \( x^2 - 2x + c = 0 \) given that one root is thrice the other, we can follow these steps: ### Step 1: Define the roots Let one root be \( \alpha \) and the other root be \( 3\alpha \) (since one root is thrice the other). ### Step 2: Use the sum of the roots According to Vieta's formulas, the sum of the roots of the quadratic equation \( ax^2 + bx + c = 0 \) is given by: \[ \text{Sum of roots} = -\frac{b}{a} \] For our equation \( x^2 - 2x + c = 0 \): - \( a = 1 \) - \( b = -2 \) Thus, the sum of the roots is: \[ \alpha + 3\alpha = -\frac{-2}{1} = 2 \] This simplifies to: \[ 4\alpha = 2 \] ### Step 3: Solve for \( \alpha \) Now, we can solve for \( \alpha \): \[ \alpha = \frac{2}{4} = \frac{1}{2} \] ### Step 4: Use the product of the roots Next, we use the product of the roots, which is given by: \[ \text{Product of roots} = \frac{c}{a} \] For our equation: \[ \alpha \cdot 3\alpha = \frac{c}{1} \] Substituting \( \alpha \): \[ \left(\frac{1}{2}\right) \cdot 3\left(\frac{1}{2}\right) = c \] This simplifies to: \[ \frac{3}{4} = c \] ### Final Answer Thus, the value of \( c \) is: \[ \boxed{\frac{3}{4}} \] ---

To find the value of \( c \) in the equation \( x^2 - 2x + c = 0 \) given that one root is thrice the other, we can follow these steps: ### Step 1: Define the roots Let one root be \( \alpha \) and the other root be \( 3\alpha \) (since one root is thrice the other). ### Step 2: Use the sum of the roots According to Vieta's formulas, the sum of the roots of the quadratic equation \( ax^2 + bx + c = 0 \) is given by: \[ ...
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