MHB Taking Image of a curve about a given line

  • Thread starter Thread starter DaalChawal
  • Start date Start date
  • Tags Tags
    Curve Image Line
Click For Summary
To find the image of the function f(x) = x + sin(x) about the line y = -x, the reflection can be expressed as x = y + sin(y), which does not yield an explicit solution for y. The discussion explores whether images can be taken about functions, noting that reflections are typically defined with respect to points or lines. The functions f(x) and its reflection exhibit symmetry around the line y = x and intersect at the point (2π, 2π). The area under the reflected function g between specified limits is calculated to be 2π², leading to a final answer of 2. The exploration highlights the complexities of function reflections and their geometric interpretations.
DaalChawal
Messages
85
Reaction score
0
Screenshot (95).png


How to find image of $f(x)= x + sinx$ about the given line $y = - x$ .

Similarly can we take image of a function about a function? OR is it necessary about which we take image should be a point, line only?
 
Mathematics news on Phys.org
If $y=x+\sin x$, then the reflection around $y=-x$ is $-x=-y+\sin(-y)$ or $x=y+\sin y$. Although a function, this cannot be explicitly solved for $y$. However the two functions are also symmetric around $y=x$ and intersect at the point $(2\pi,2\pi)$. So the area under $g$ between your limits is $2\pi^2$ so your answer is $2$.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 29 ·
Replies
29
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
Replies
3
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 2 ·
Replies
2
Views
1K