Dimensions of identity matrix | Matrices | Precalculus | Khan Academy

Missed the previous lesson?

Precalculus on Khan Academy: You may think that precalculus is simply the course you take before calculus. You would be right, of course, but that definition doesn't mean anything unless you have some knowledge of what calculus is. Let's keep it simple, shall we? Calculus is a conceptual framework which provides systematic techniques for solving problems. These problems are appropriately applicable to analytic geometry and algebra. Therefore....precalculus gives you the background for the mathematical concepts, problems, issues and techniques that appear in calculus, including trigonometry, functions, complex numbers, vectors, matrices, and others. There you have it ladies and gentlemen....an introduction to precalculus!

About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.

For free. For everyone. Forever. #YouCanLearnAnything

Subscribe to Khan Academy’s Precalculus channel:

[SaadUsmanTariq]

One word is enough to define this video:

AMAZING!!!!

[anubisjishin]

2019 and yet your video are still amazing! Thanks for all the help during this course.

[alektad]

This reminds me of Khan Academy older videos, there is something very positively entertaining when Sal messes up :) 

[widenesslock]

Ty sir you u make us play and enjoy with the mathematics

[premchandak]

1:30 its only possible in maths to have 'a columns'.

[phakirmohan]

2:25 sooner i realised that a non-square matrix really can't have a identity matrix 😢

[satejraste]

I HAVE A DOUBT ABOUT IDENTITY MATRIX HERE, WE TOOK EXAMPLE OF 1*X=X BUT X*1=X SO IN BOTH CASE OF MATRIX IT SHOULD BE TRUE BUT IF WE DO I.A AND A.I IT SOULD BE SAME BUT THEY BOTH DIFFER PLZ EXPLAIN?

[zuixyqw]

what is this crap. Oh well, I'll just keep trying and going.