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

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SUMMARY

The composite transformation H, defined as H = H1 * H2 * H3, involves three distinct transformations: H1 is a reflection about the line y = x + 1, H2 is a counterclockwise rotation of π/2 about the point (1,0), and H3 is a translation by 1 - i. To visualize the transformation H, one must apply H3 first, followed by H2, and finally H1. The discussion highlights the challenge of visualizing the rotation about the point (1,0), particularly in maintaining the correct counterclockwise direction.

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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.
 

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Red triangle shows the correct rotation of $\dfrac{\pi}{2}$ CCW. Yours appears to be in the CW direction.

54E20B4D-C6B8-4531-B74B-74F50F2F0EB6.jpeg
 

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