How Does the Composite Transformation H Affect a Triangle and Arrow?

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lemonthree
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Given that
$$
H_{1} $$= reflection about the line y = x + 1;
$$H_{2} $$= counterclockwise rotation of pi/2 about the point (1,0);
$$H_{3} $$= translation by 1 - i.
What is the image of the triangle and arrow under the map $$ H = H_{1} *H_{2} * H_{3} $$?

I need help visualising the above transformation H. I know that $$ H = H_{1} *H_{2} * H_{3} $$, so we must perform the transformations from right to left (H3 first, then H2, and lastly H1). Now, in a question that provides the equation for $$ H_{1},H_{2} , H_{3} $$, I believe I can solve this by substituting the values into $$ H_{1},H_{2} , H_{3} $$ respectively. However, in this case, the question does not provide the equation and it is up to my visualisation.

I have attached photos showing my steps for each respectively. I have no trouble with translation (H3) as it is relatively easy to visualise.
However, I struggle a little for the rotation about (1,0). I can't quite visualise "pivoting" the arrow and triangle about (1,0)...I would like to ask for some tips to aid in visualising such rotations better.
 
Attachments
  • Coordinate grid from -4 to 4 on both axes with a blue right triangle with vertices at (0,0), (0,1) and (1,0), and a green arrow pointing left with its tip at (-2,2).
    original.png
    4.2 KB · Views: 161
  • Coordinate grid from -4 to 4 on both axes showing a dark blue right triangle with vertices at (0,0), (0,1) and (1,0), and a light green arrow pointing left with its tip at (-2,2).
    H3.png
    4.2 KB · Views: 168
  • Coordinate grid from -4 to 4 on both axes showing a blue right triangle with vertices near (0,0), (0,-1) and (2,-1), a green arrow pointing left at (0,1) and a green arrow pointing down at (0,-2), and a black plus-shaped marker at (1,0).
    H2.png
    4.3 KB · Views: 177
  • Coordinate grid from -4 to 4 on both axes showing a red line y = x + 1, a blue triangle with a green arrow pointing left near (-2, 1), and a second blue triangle with a green arrow pointing down near (0, -1), with black crosses marking points.
    H1.png
    7.6 KB · Views: 168
  • Coordinate grid from -4 to 4 on both axes showing a blue right triangle with vertices near (-1,3), (0,3) and (-1,2), and a green left-pointing arrow centred around (-3,1).
    answer.JPG
    14.9 KB · Views: 142
Red triangle shows the correct rotation of $\dfrac{\pi}{2}$ CCW. Yours appears to be in the CW direction.

Coordinate plane with x and y axes showing a black unit triangle at the origin, a red triangle to its right, a blue triangle below the red one, a magenta triangle upper left, and the line f1(x)=x+1 in blue.