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What is the range of this quadratic function?\newliney=x24x12y = x^2 - 4x - 12\newlineChoices:\newline(A)yy16{y | y \geq -16}\newline(B)yy2{y | y \geq 2}\newline(C)yy16{y | y \geq 16}\newline(D)all real numbers

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Q. What is the range of this quadratic function?\newliney=x24x12y = x^2 - 4x - 12\newlineChoices:\newline(A)yy16{y | y \geq -16}\newline(B)yy2{y | y \geq 2}\newline(C)yy16{y | y \geq 16}\newline(D)all real numbers
  1. Find Vertex: We have the quadratic function y=x24x12y = x^2 - 4x - 12. To find the range, we need to determine the vertex of the parabola. The xx-coordinate of the vertex can be found using the formula x=b2ax = -\frac{b}{2a}, where aa is the coefficient of x2x^2 and bb is the coefficient of xx.\newlineSubstitute a=1a = 1 and b=4b = -4 into the formula.\newlinex=(4)/(21)x = -(-4)/(2\cdot1)\newlinexx00\newlinexx11
  2. 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=2x = 2 into the original equation.\newliney=(2)24(2)12y = (2)^2 - 4(2) - 12\newliney=4812y = 4 - 8 - 12\newliney=16y = -16
  3. Determine Parabola Direction: The vertex of the parabola is at the point (2,16)(2, -16). Since the coefficient of x2x^2 is positive (a=1)(a = 1), the parabola opens upwards. This means that the vertex represents the minimum point on the graph of the quadratic function.
  4. Identify Range: Since the parabola opens upwards and the yy-coordinate of the vertex is the minimum value that yy can take, the range of the function is all yy-values greater than or equal to the yy-coordinate of the vertex.\newlineRange: {yy16}\{y | y \geq -16\}

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