Question 1
Let and g(x)=x-5, for .
Question 1(a)
Find f(8).
Question 1(b)
Find .
Question 1(c)
Solve .
EduNinjaLet f(x)=x2+2x+1 and g(x)=x-5, for x∈R.
Find f(8).
Find (g∘f)(x).
Solve (g∘f)(x)=0.
Kiran and Logan collect the following data about the river Afon, where x is the distance in metres from the source and y is the depth in centimetres.

This data is represented in the following scatter diagram.

Kiran knows that the depth of the river is 0 cm at the source.
Kiran calculates xˉ and yˉ for the seven points given in the table on page 2 and draws a line on the scatter diagram through the mean point (xˉ,yˉ) and the point (0,0).
Find
the equation of Kiran's line.
For the seven points given in the table Logan finds the regression line of y on x with equation y=a x+b, where a,b∈R.
The following table shows values of f(x) and g(x) for different values of x.
Both f and g are one-to-one functions.

Find g(0).
Find (f∘g)(0).
Find the value of x such that f(x)=0.
The graph of y=f(x) for −4≤x≤6 is shown in the following diagram.

Write down the value of
f(2);
(f∘f)(2).
Let g(x)=21f(x)+1 for −4≤x≤6. On the axes above, sketch the graph of g.
Consider the function f(x)=x2+x+x50,x=0.
Find f(1).
Solve f(x)=0.
The graph of f has a local minimum at point A .
Consider the function f(x)=-2(x-1)(x+3), for x∈R. The following diagram shows part of the graph of f.

For the graph of f
find the x-coordinates of the x-intercepts;
find the coordinates of the vertex.
The function f can be written in the form f(x)=−2(x−h)2+k.
Write down the value of h and the value of k.
Let f(x)=8x−2x2. Part of the graph of f is shown below.

Find the x-intercepts of the graph.
Write down the equation of the axis of symmetry.
Find the y-coordinate of the vertex.
Let f(x)=p(x-q)(x-r). Part of the graph of f is shown below.

The graph passes through the points (-2,0),(0,-4) and (4,0).
Write down the value of q and of r.
Write down the equation of the axis of symmetry.
Find the value of p.
Let f be a quadratic function. Part of the graph of f is shown below.

The vertex is at P(4,2) and the y-intercept is at Q(0,6).
Write down the equation of the axis of symmetry.
The function f can be written in the form f(x)=a(x−h)2+k.
Write down the value of h and of k.
Find a.
Let f(x)=x+2 for x≥−2 and g(x)=3 x-7 for x∈R.
Write down f(14).
Find (g∘f)(14).
Find g−1(x).