Q. What is the range of this quadratic function?y=x2+2x−15Choices:(A)y∣y≥−16(B)y∣y≤−16(C)y∣y≥−1(D)all real numbers
Identify Quadratic Function: Identify the quadratic function and its coefficients.The given quadratic function is y=x2+2x−15. The coefficients are a=1, b=2, and c=−15.
Find Vertex x-coordinate: Find the x-coordinate of the vertex.The x-coordinate of the vertex of a parabola given by y=ax2+bx+c is found using the formula x=−2ab. Here, a=1 and b=2.x=−2⋅12x=−22x=−1
Find Vertex y-coordinate: Find the y-coordinate of the vertex by substituting x=−1 into the quadratic function.y=(−1)2+2(−1)−15y=1−2−15y=−16
Determine Parabola Direction: Determine the direction in which the parabola opens.Since the coefficient a=1 is positive, the parabola opens upwards.
Find Range: Find the range of the quadratic function.The vertex of the parabola is (−1,−16), and since the parabola opens upwards, the y-values will be greater than or equal to the y-coordinate of the vertex.Range: \{y∣y≥−16\}
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