Multiplying Upper Triangular Matrices

[@ILoveMaths07]

Perfect! Absolutely loved your clear explanation. Have been struggling with the sigma notation in matrix multiplication for over a decade. Finally got it!

[@sirshabiswas3010]

Welcome back, Excellent Teacher! Not to mention but I was genuinely worried about you.

[@pedropauloburigobastos]

Good to see you back!! I really miss the videos, hugs from Brazil

[@Mohamed.Soltan1991]

Welcome back 💖💖🌹🌹🌹

[@user-wu8yq1rb9t]

You back ....🎉 Great... Welcome back

[@tomkerruish2982]

Welcome back! I was getting worried. Now, how about some cool Ma 108 or Ma 120 stuff?😁

[@slavinojunepri7648]

Nice proof

[@alipourzand6499]

Nice propf. What about consideting the determonant of the product of two upper triangular matrix which is the product of the determinant. And since the determinant of a triangular matrix is the product of the diagonal, this will imply that the diagonal of the resulting matrix is the product of the diagonals. Is this a sufficent condition to proove that?

[@MuPrimeMath]

You could use the result in the video to compute the determinant of the product of two upper triangular matrices. However, you cannot use the determinant to prove what the diagonal entries are, because there are many possible diagonal entries that could multiply to the same determinant. For example, [[1,0],[0,6]] and [[2,0],[0,3]] both have determinant 6.

[@cycklist]

Long time no see

[@alejrandom6592]

First proof is nice, but you can make it nicer by using some notation and using contrapositive

[@alejrandom6592]

Amazing video as always though