Complete square then find vertex/turning point

A question is this type if and only if it requires completing the square to find or state the coordinates of the vertex, minimum point, or maximum point of a parabola.

24 questions · Moderate -0.9

1.02e Complete the square: quadratic polynomials and turning points
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OCR C1 Specimen Q2
5 marks Moderate -0.8
2
  1. Express \(x ^ { 2 } - 8 x + 3\) in the form \(( x + a ) ^ { 2 } + b\).
  2. Hence write down the coordinates of the minimum point on the graph of \(y = x ^ { 2 } - 8 x + 3\).
OCR MEI C1 Q2
4 marks Moderate -0.8
2
  1. Find the constants \(a\) and \(b\) such that, for all values of \(x\), $$x ^ { 2 } + 4 x + 14 = ( x + a ) ^ { 2 } + b$$
  2. Write down the greatest value of \(\frac { 1 } { x ^ { 2 } + 4 x + 14 }\).
OCR C1 Q4
5 marks Easy -1.2
4. (i) Express \(x ^ { 2 } + 6 x + 7\) in the form \(( x + a ) ^ { 2 } + b\).
(ii) State the coordinates of the vertex of the curve \(y = x ^ { 2 } + 6 x + 7\).
OCR MEI C1 Q1
5 marks Moderate -0.8
1 Express \(5 x ^ { 2 } + 15 x + 12\) in the form \(a ( x + b ) ^ { 2 } + c\).
Hence state the minimum value of \(y\) on the curve \(y = 5 x ^ { 2 } + 15 x + 12\).
OCR C1 2016 June Q6
6 marks Moderate -0.8
6
  1. Express \(4 + 12 x - 2 x ^ { 2 }\) in the form \(a ( x + b ) ^ { 2 } + c\).
  2. State the coordinates of the maximum point of the curve \(y = 4 + 12 x - 2 x ^ { 2 }\).
OCR MEI C1 2012 January Q8
5 marks Moderate -0.8
8 Express \(5 x ^ { 2 } + 15 x + 12\) in the form \(a ( x + b ) ^ { 2 } + c\).
Hence state the minimum value of \(y\) on the curve \(y = 5 x ^ { 2 } + 15 x + 12\).
OCR H240/01 2022 June Q4
8 marks Moderate -0.8
4
  1. Write \(2 x ^ { 2 } + 6 x + 7\) in the form \(p ( x + q ) ^ { 2 } + r\), where \(p , q\) and \(r\) are constants.
  2. State the coordinates of the minimum point on the graph of \(y = 2 x ^ { 2 } + 6 x + 7\).
  3. Hence deduce
Edexcel AS Paper 1 2021 November Q14
10 marks Standard +0.3
  1. A curve \(C\) has equation \(y = \mathrm { f } ( x )\) where
$$f ( x ) = - 3 x ^ { 2 } + 12 x + 8$$
  1. Write \(\mathrm { f } ( x )\) in the form $$a ( x + b ) ^ { 2 } + c$$ where \(a\), \(b\) and \(c\) are constants to be found. The curve \(C\) has a maximum turning point at \(M\).
  2. Find the coordinates of \(M\). \begin{figure}[h]
    \includegraphics[alt={},max width=\textwidth]{235cd1dc-a3ab-473a-bf77-3e41b274dfd8-34_735_841_913_612} \captionsetup{labelformat=empty} \caption{Figure 3}
    \end{figure} Figure 3 shows a sketch of the curve \(C\).
    The line \(l\) passes through \(M\) and is parallel to the \(x\)-axis.
    The region \(R\), shown shaded in Figure 3, is bounded by \(C , l\) and the \(y\)-axis.
  3. Using algebraic integration, find the area of \(R\).
Edexcel Paper 1 2021 October Q2
4 marks Easy -1.8
  1. Given that
$$\mathrm { f } ( x ) = x ^ { 2 } - 4 x + 5 \quad x \in \mathbb { R }$$
  1. express \(\mathrm { f } ( x )\) in the form \(( x + a ) ^ { 2 } + b\) where \(a\) and \(b\) are integers to be found. The curve with equation \(y = \mathrm { f } ( x )\)
    • meets the \(y\)-axis at the point \(P\)
    • has a minimum turning point at the point \(Q\)
    • Write down
      1. the coordinates of \(P\)
      2. the coordinates of \(Q\)
OCR PURE Q2
6 marks Moderate -0.8
2
  1. Express \(5 x ^ { 2 } - 20 x + 3\) in the form \(p ( x + q ) ^ { 2 } + r\), where \(p , q\) and \(r\) are integers.
  2. State the coordinates of the minimum point of the curve \(y = 5 x ^ { 2 } - 20 x + 3\).
  3. State the equation of the normal to the curve \(y = 5 x ^ { 2 } - 20 x + 3\) at its minimum point.
OCR MEI AS Paper 2 2023 June Q2
3 marks Easy -1.2
2
  1. Express \(x ^ { 2 } - 6 x + 1\) in the form \(( \mathrm { x } - \mathrm { a } ) ^ { 2 } - \mathrm { b }\), where \(a\) and \(b\) are integers to be determined.
  2. Hence state the coordinates of the turning point on the graph of \(y = x ^ { 2 } - 6 x + 1\).
Edexcel C1 Q6
8 marks Moderate -0.8
6. \(f ( x ) = x ^ { 2 } - 10 x + 17\).
  1. Express \(\mathrm { f } ( x )\) in the form \(a ( x + b ) ^ { 2 } + c\).
  2. State the coordinates of the minimum point of the curve \(y = \mathrm { f } ( x )\).
  3. Deduce the coordinates of the minimum point of each of the following curves:
    1. \(\quad y = \mathrm { f } ( x ) + 4\),
    2. \(y = \mathrm { f } ( 2 x )\).
AQA C1 2008 January Q5
9 marks Moderate -0.8
5
  1. Factorise \(9 - 8 x - x ^ { 2 }\).
  2. Show that \(25 - ( x + 4 ) ^ { 2 }\) can be written as \(9 - 8 x - x ^ { 2 }\).
  3. A curve has equation \(y = 9 - 8 x - x ^ { 2 }\).
    1. Write down the equation of its line of symmetry.
    2. Find the coordinates of its vertex.
    3. Sketch the curve, indicating the values of the intercepts on the \(x\)-axis and the \(y\)-axis.
Pre-U Pre-U 9794/1 2014 June Q1
5 marks Easy -1.2
1
  1. Express \(x ^ { 2 } - 8 x + 10\) in the form \(( x - a ) ^ { 2 } + b\) where \(a\) and \(b\) are integers to be found.
  2. Hence write down the minimum value of \(x ^ { 2 } - 8 x + 10\) and the corresponding value of \(x\).
WJEC Unit 3 2022 June Q12
Standard +0.3
The diagram below shows a sketch of the graph of \(y = f ( x )\), where $$f ( x ) = 2 x ^ { 2 } + 12 x + 10 .$$ The graph intersects the \(x\)-axis at the points \(( p , 0 ) , ( q , 0 )\) and the \(y\)-axis at the point \(( 0,10 )\). \includegraphics[max width=\textwidth, alt={}, center]{72bb1603-edbd-4e2e-bf2b-f33bb667e61b-5_1004_1171_648_440}
a) Write down the value of \(f f ( p )\).
b) Determine the values of \(p\) and \(q\).
c) Express \(f ( x )\) in the form \(a ( x + b ) ^ { 2 } + c\), where \(a , b , c\) are constants whose values are to be found. Write down the coordinates of the minimum point.
d) Explain why \(f ^ { - 1 } ( x )\) does not exist.
e) The function \(g ( x )\) is defined as $$g ( x ) = f ( x ) \quad \text { for } \quad - 3 \leqslant x < \infty .$$ i) Find an expression for \(g ^ { - 1 } ( x )\).
ii) Sketch the graph of \(y = g ^ { - 1 } ( x )\), indicating the coordinates of the points where the graph intersects the \(x\)-axis and the \(y\)-axis.
CAIE P1 2018 November Q9
7 marks Moderate -0.8
The function f is defined by \(\text{f} : x \mapsto 2x^2 - 12x + 7\) for \(x \in \mathbb{R}\).
  1. Express \(2x^2 - 12x + 7\) in the form \(2(x + a)^2 + b\), where \(a\) and \(b\) are constants. [2]
  2. State the range of f. [1]
The function g is defined by \(\text{g} : x \mapsto 2x^2 - 12x + 7\) for \(x \leqslant k\).
  1. State the largest value of \(k\) for which g has an inverse. [1]
  2. Given that g has an inverse, find an expression for \(\text{g}^{-1}(x)\). [3]
OCR C1 2013 June Q4
7 marks Moderate -0.8
  1. Express \(3x^2 + 9x + 10\) in the form \(3(x + p)^2 + q\). [3]
  2. State the coordinates of the minimum point of the curve \(y = 3x^2 + 9x + 10\). [2]
  3. Calculate the discriminant of \(3x^2 + 9x + 10\). [2]
OCR MEI C1 2009 June Q9
5 marks Easy -1.2
  1. Express \(x^2 + 6x + 5\) in the form \((x + a)^2 + b\). [3]
  2. Write down the coordinates of the minimum point on the graph of \(y = x^2 + 6x + 5\). [2]
OCR MEI C1 2013 June Q8
5 marks Moderate -0.8
Express \(3x^2 - 12x + 5\) in the form \(a(x - b)^2 - c\). Hence state the minimum value of \(y\) on the curve \(y = 3x^2 - 12x + 5\). [5]
Edexcel C1 Q2
4 marks Easy -1.2
  1. Express \(x^2 + 6x + 7\) in the form \((x + a)^2 + b\). [3]
  2. State the coordinates of the minimum point of the curve \(y = x^2 + 6x + 7\). [1]
OCR MEI C1 Q6
5 marks Moderate -0.8
Express \(3x^2 - 12x + 5\) in the form \(a(x - b)^2 - c\). Hence state the minimum value of \(y\) on the curve \(y = 3x^2 - 12x + 5\). [5]
AQA AS Paper 2 Specimen Q4
3 marks Moderate -0.8
Find the coordinates, in terms of \(a\), of the minimum point on the curve \(y = x^2 - 5x + a\), where \(a\) is a constant. Fully justify your answer. [3 marks]
SPS SPS SM Mechanics 2022 February Q2
4 marks Easy -1.8
Given that $$f(x) = x^2 - 4x + 5 \quad x \in \mathbb{R}$$
  1. express \(f(x)\) in the form \((x + a)^2 + b\) where \(a\) and \(b\) are integers to be found. [2]
The curve with equation \(y = f(x)\) • meets the \(y\)-axis at the point \(P\) • has a minimum turning point at the point \(Q\)
  1. Write down
    1. the coordinates of \(P\)
    2. the coordinates of \(Q\)
    [2]
SPS SPS SM 2022 October Q2
5 marks Easy -1.3
A curve \(C\) has equation \(y = f(x)\) where $$f(x) = -3x^2 + 12x + 8$$
  1. Write \(f(x)\) in the form $$a(x + b)^2 + c$$ where \(a\), \(b\) and \(c\) are constants to be found. [3]
The curve \(C\) has a maximum turning point at \(M\).
  1. Find the coordinates of \(M\). [2]