Q. What is the range of this quadratic function?y=x2−4x−12Choices:(A)y∣y≥−16(B)y∣y≥2(C)y∣y≥16(D)all real numbers
Find Vertex: We have the quadratic function y=x2−4x−12. To find the range, we need to determine the vertex of the parabola. The x-coordinate of the vertex can be found using the formula x=−2ab, where a is the coefficient of x2 and b is the coefficient of x.Substitute a=1 and b=−4 into the formula.x=−(−4)/(2⋅1)x0x1
Calculate y-coordinate: Now that we have the x-coordinate of the vertex, we need to find the corresponding y-coordinate. We do this by substituting x=2 into the original equation.y=(2)2−4(2)−12y=4−8−12y=−16
Determine Parabola Direction: The vertex of the parabola is at the point (2,−16). Since the coefficient of x2 is positive (a=1), the parabola opens upwards. This means that the vertex represents the minimum point on the graph of the quadratic function.
Identify Range: Since the parabola opens upwards and the y-coordinate of the vertex is the minimum value that y can take, the range of the function is all y-values greater than or equal to the y-coordinate of the vertex.Range: {y∣y≥−16}
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