Direction: In the following questions, a statement of assertion (A) i...
As the polynomial is x
2 - 2kx + 2 and its zeros are equal but opposition sign, sum of zeroes must be zero.
sum of zeros = 0
Assertion (A) is false but reason (R) is true.
Thus (d) is correct option.
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Direction: In the following questions, a statement of assertion (A) i...
Assertion: If both zeros of the quadratic polynomial x^2 - 2kx + 2 are equal in magnitude but opposite in sign, then the value of k is 1/2.
Reason: The sum of the zeros of a quadratic polynomial ax^2 + bx + c is -b/a.
The correct answer is option D, Assertion (A) is false but reason (R) is true.
Explanation:
Let's solve the quadratic polynomial x^2 - 2kx + 2 to find its zeros.
The quadratic polynomial can be factored as (x - r)(x + r) = 0, where r is the magnitude of the zeros.
Expanding the equation, we get x^2 + rx - rx - r^2 = 0.
This simplifies to x^2 - r^2 = 0.
So, the zeros of the quadratic polynomial are x = ±r.
According to the given assertion, the zeros are equal in magnitude but opposite in sign. This means that r is a non-zero value.
Therefore, the zeros of the quadratic polynomial are x = r and x = -r.
Using the sum of zeros formula for the quadratic polynomial ax^2 + bx + c, we have:
Sum of zeros = -b/a
In this case, the sum of zeros is r + (-r) = 0.
Comparing this with the formula, we have -b/a = 0.
To satisfy this equation, b must be equal to 0.
However, in the original quadratic polynomial x^2 - 2kx + 2, the coefficient of x is -2k, not 0.
Therefore, the assertion is false.
However, the reason is true because the sum of zeros of any quadratic polynomial is given by -b/a.
Hence, the correct answer is option D: Assertion (A) is false but reason (R) is true.
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