From Tom: Hi! I am a woodworker who needs some help finding a formula. I have to make a cylinder shape column that butts up against a sloped ceiling using bending plywood. I need to figure out how to cut the shape on this flat piece of material. The diameter of the column is 54.375". The tallest point is 9 13/16" and the shortest point is 4 7/16". Any help would be greatly appreciated. Answered by Harley Weston.
From Kendra: i have to prove that tangents to a circle at the endpoints of a diatmeter are parallel by stating whats given, whats to prove and a plane, then write a two column proof i dont understand this Answered by Stephen La Rocque.
From Sue: Question 1
Suppose all matrices in the equation below are square and invertible. Solve for x .
BA-1XB-1 + 2BA + In = 0 (the symbol "0" here denotes the matrix of all 0's in it)
Also, A-1 or B-1 is indicating inverse and "In" = for example, A-1 times A
I hope you understand the above. I have to show all the steps.
Suppose we consider the set of all 2x2 matrices along with the operations of matrix addition and multiplication. Do they form a field? Why or why not?
I think the answer is no because under multiplication it is not commutative and not all square matrices are invertible. I not positive so I'd like some help. Answered by Penny Nom.
From Marcelo: I want to know if is it possible to solve this problem:
I have an empty NxM matrix and I know totals (sum) by rows and totals by column.
Is there any algorithm to fill the matrix so that the summary of columns and rows gives the original values I have? Answered by Harley Weston.
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