Matrices Quick Tip for Rotating and Reflecting

Quick tips for remembering the matrices that rotate and reflect in this free math video tutorial by Mario's Math Tutoring. We go through reflecting over the x-axis, y-axis, y=x, Rotation 90, Rotation 180, and Rotation 270.

0:24 Technique for Remembering the Rotation Matrices
0:53 Definition of the Identity Matrix
1:19 Rotation 90 Degrees
1:49 Rotation 180 Degrees
2:12 Rotation 270 Degrees
2:25 Reflection Over x Axis
2:40 Reflection Over y Axis
2:55 Reflection Over Line y=x
3:07 Reflecting (3,1) Over y=x

Related Videos:

Coordinate Rules for Rotating and Reflecting (Not Matrices)

My Video Playlist of More Matrices Videos

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[romnyeverett]

this 4 minute video > a whole month of my additional mathematics class

[AdulTFansClubMan]

extremely clear concept, you helped me shorten the learning time from 2 hours to a few minutes

[disasterstruck]

i have a further maths exam in an hour you have just saved my life

[priyambandyopadhyay]

Thanks a lot. I was having extreme difficulty in understanding these concept, but this video proved a boon for me.

Extremely thankful to you.

[Saad-rmsd]

And my teacher was like just memorize it.

[christianpeterson]

thank you for helping. i came back from covid into a test of things i didn’t know how to do. now i fell better for my retest

[yaweli]

I wanted to like your video multiple times but realized it wasn’t rotationally possible.Thanks.

[someonefromnomansland]

I LOVE YOU THANK THANK YOU SO SO MUCH [cries NO more in Spain (the s is silent)]

[sumyazakir]

You're a life saviour. I didn't have problems with maths but remembering the matrices was the problem and now it's all good now. Thanks to you!

[dalisabe]

This is discrete rotation by a right angle. If we wish to achieve continuous rotation by some random angle x, we replace the ones in the rotation matrix with cos(x) and sin(x) associated with the proper sign. Thank you so much for this presentation. It was very informative and stimulant.

[muhamednajeebk]

Very simple explanation...thank you very much...

[mohanadmohamed]

Easy to understand Thx, You help me alot.

[lohanygarcia]

Love this video! Very clear and easy to understand!

[Jey]

Thanks a lot... I finally understand that.

[dylan-ktkd]

i dont understand why school teachers teach so blunt, no proof or intuition for anything making math way harder than it should be. That being said im grateful that channels like this exist

[justjacqueline]

Succinct to the point, how refreshing.

[eduardorivera]

Amazing! It took my professor two lectures to explain this and I didnt understand it until now. It's awesome how clear that was! Thank you! Will you be doing any college level math videos? Multi variable Calc? Diff. equations?

[nirdeshlamsal]

thank you sir... i was struggling for a month to get this
now i got it

[haroonrasheed]

You make it very easy to understand and saves a lot of my time.

[nurulsolehah]

Thank you so much. This might just save me my Maths grades.