What is the sum of the roots of all the quadratic equations that can b...
The equations formed by the roots of the equation
(x – a) (x – b)(x – c) can be as follows:
(i) (x – a)(x – b) ⇒ Roots are a, b
(ii) (x – b)(x – c) ⇒ Roots are b, c
(iii) (x – c)(x – a) ⇒ Roots are c, a
(iv) (x – a)2 ⇒ Roots are a, a
(v) (x – b)2 ⇒ Roots are b, b
(vi) (x – c)2 ⇒ Roots are c, c
Adding all these roots, we get 4(a + b + c).
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What is the sum of the roots of all the quadratic equations that can b...
The quadratic equation (x - a)(x - b) = 0, where a and b are the roots, can be expanded as x^2 - (a + b)x + ab = 0.
For the quadratic equation to have roots in common with (x - a)(x - b) = 0, the discriminant of (x - a)(x - b) = 0, which is (a + b)^2 - 4ab, must be zero.
Setting the discriminant to zero, we have (a + b)^2 - 4ab = 0.
Expanding this equation, we get a^2 + 2ab + b^2 - 4ab = 0.
Simplifying, we have a^2 - 2ab + b^2 = 0.
This equation can be factored as (a - b)^2 = 0.
Taking the square root of both sides, we have a - b = 0.
Therefore, the sum of the roots of all the quadratic equations that can be formed such that both the roots of the quadratic equation are common with the roots of (x - a)(x - b) = 0 is a + b.
So, the sum of the roots is a + b.
What is the sum of the roots of all the quadratic equations that can b...
The equations formed by the roots of the equation
(x – a) (x – b)(x – c) can be as follows:
(i) (x – a)(x – b) ⇒ Roots are a, b
(ii) (x – b)(x – c) ⇒ Roots are b, c
(iii) (x – c)(x – a) ⇒ Roots are c, a
(iv) (x – a)2 ⇒ Roots are a, a
(v) (x – b)2 ⇒ Roots are b, b
(vi) (x – c)2 ⇒ Roots are c, c
Adding all these roots, we get 4(a + b + c).
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