This problem involves finding the value of a coefficient in a quadratic equation based on the nature of its roots. The key is understanding the condition for real and equal roots.
The given quadratic equation is:
$$kx^2 – 4x + 1 = 0$$
For a general quadratic equation of the form $ax^2 + bx + c = 0$, we can identify the coefficients:
A quadratic equation has real and equal roots when its discriminant is equal to zero. The discriminant ($D$) is calculated using the formula:
$$D = b^2 - 4ac$$
The condition for real and equal roots is:
$$D = 0$$
We substitute the coefficients ($a=k$, $b=-4$, $c=1$) into the discriminant formula and set it to zero:
$$(-4)^2 - 4(k)(1) = 0$$
$$16 - 4k = 0$$
$$16 = 4k$$
Divide both sides by 4:
$$k = \frac{16}{4}$$
$$k = 4$$
Therefore, the value of k that makes the roots of the quadratic equation $kx^2 – 4x + 1 = 0$ real and equal is 4.
Find the minimum value of 2x² – 5x – 3 and also find x.
A quadratic equation $x^2 + 3x + k = 0$ has a discriminant equal to 9. What is the value of k?
If both roots of the quadratic equation, $x^2 + 3x + 2 = 0$, are also roots of another quadratic equation, $ax^2 + bx + c = 0$, then which of the following must be true?