Figure 1 shows a sketch of the curve with equation $y = f(x)$, $x > 0$, where $f$ is an increasing function of $x$ - Edexcel - A-Level Maths Pure - Question 3 - 2013 - Paper 8
Question 3
Figure 1 shows a sketch of the curve with equation $y = f(x)$, $x > 0$, where $f$ is an increasing function of $x$. The curve crosses the $x$-axis at the point $(1, ... show full transcript
Worked Solution & Example Answer:Figure 1 shows a sketch of the curve with equation $y = f(x)$, $x > 0$, where $f$ is an increasing function of $x$ - Edexcel - A-Level Maths Pure - Question 3 - 2013 - Paper 8
Step 1
Sketch the curve with equation $y = f(2x)$, $x > 0$
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The function f(2x) indicates a horizontal compression of the function f(x) by a factor of 2. This means the graph will maintain its shape but will cross the x-axis at half the original point for x=1. So, it crosses the x-axis at (0.5,0). The general shape will be an increasing curve that approaches the y-axis asymptotically and rises after crossing the x-axis.
Step 2
Sketch the curve with equation $y = |f(x)|$, $x > 0$
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The absolute value function ∣f(x)∣ negates any negative values of f(x). As f(x) crosses the x-axis at (1,0), the graph will have a cusp at this point, reflecting any negative portion of the curve upwards above the x-axis. Thus, it will intersect the x-axis only at (1,0) and continue increasing positively from there.