IB myp 4-5 MATHEMATICS – Practice Questions- All Topics
Topic :Geometry-Movement on a plane-isometric transformations
Topic :Geometry- Weightage : 21 %
All Questions for Topic : Metric conversions,Volume of regular polyhedra,Similarity and congruence,Coordinate geometry, including distance, midpoint and gradient formulae,Movement on a plane- isometric transformations, enlargements and tessellations,y=m x+c, gradients and intercepts (see also functions),Gradient of parallel lines,Circle geometry,Rotation around a given point
Question (4 Marks)
Given that $f(x)=x^2$ and $g(x)=-4(x+2)^2+1$, identify the stages that transform $f(x)$ onto $g(x)$.
Transformation 1:……
Transformation 2:……
Transformation 3:…….
Transformation 4:……..
▶️Answer/Explanation
Ans:
To identify the stages that transform $f(x)$ into $g(x)$, let’s compare the two functions and determine the steps needed to get from $f(x)$ to $g(x)$.
Transformation 1: Reflection across the x-axis
This transformation changes the sign of the function, resulting in $-f(x)$. It can be achieved by multiplying $f(x)$ by $-1$. So, the first transformation is the reflection across the x-axis.
Transformation 2: Vertical stretch/compression
The function $g(x)$ is compressed vertically by a factor of 4 compared to $-f(x)$. To achieve this, we multiply $-f(x)$ by $\frac{1}{4}$.
Transformation 3: Horizontal shift to the left
The function $g(x)$ is a result of shifting $-\frac{1}{4}f(x)$ to the left by 2 units. This horizontal shift can be obtained by replacing $x$ with $x+2$ in the equation $-\frac{1}{4}f(x)$.
Transformation 4: Vertical shift upward
Finally, the function $g(x)$ is obtained by shifting $-\frac{1}{4}f(x+2)$ upwards by 1 unit. This vertical shift can be achieved by adding 1 to the expression $-\frac{1}{4}f(x+2)$.
Putting it all together, the stages that transform $f(x)$ into $g(x)$ are as follows:
Transformation 1: Reflection across the x-axis: $-f(x)$
Transformation 2: Vertical stretch/compression: $-\frac{1}{4}f(x)$
Transformation 3: Horizontal shift to the left: $-\frac{1}{4}f(x+2)$
Transformation 4: Vertical shift upward: $-\frac{1}{4}f(x+2)+1$
Therefore, the stages that transform $f(x)$ onto $g(x)$ are as described above.
Question (10 marks)
The following video illustrates how tidal range can be modelled over time by a sine function.
Below is the sine curve modelling the tide in Saint-Malo on a day in November 2017. $h(t)$ is the height in metres $(m)$ of water in the harbour and $t$ is the number of hours after midnight.
Question (a) : 2 marks
Determine the tidal range which is the difference between the height of the low and high tides in the harbour.
▶️Answer/Explanation
Ans:
(Min) 1 and (Max) 17
Difference = 16