Question
For a given k, what is the minimum value of x^2+kx+k^2 ?
For a given k, what is the minimum value of x^2+kx+k^2 ?
C. 3k^2 4
Let the given expression be f(x) = x^2 + kx + k^2. To find the minimum value, we can complete the square for the quadratic expression in x: f(x) = x^2 + kx + k^2 4 - k^2 4 + k^2 f(x) = (x + k 2 )^2 + 3k^2 4 Since the square of a real number is always non-negative, (x + k 2 )^2 0 for all real x. The minimum value of f(x) occurs when x = - k 2 . Therefore, the minimum value of the expression is 3k^2 4 . Answer: 3k^2 4
Related: Mathematics — Quadratic Equation · All PYQ Banks