Answer:
A), B) and D) are true
Step-by-step explanation:
A) We can prove it as follows:
B) When you compute the product Ax, the i-th component is the matrix of the i-th column of A with x, denote this by Ai x. Then, we have that 
. Now, the colums of A are orthonormal so we have that (Ai x)^2=x_i^2. Then 
.
C) Consider 
. This set is orthogonal because 
, but S is not orthonormal because the norm of (0,2) is 2≠1.
D) Let A be an orthogonal matrix in 
. Then the columns of A form an orthonormal set. We have that 
. To see this, note than the component 
of the product 
is the dot product of the i-th row of 
and the jth row of 
. But the i-th row of is equal to the i-th column of . If i≠j, this product is equal to 0 (orthogonality) and if i=j this product is equal to 1 (the columns are unit vectors), then 
E) Consider S={e_1,0}. S is orthogonal but is not linearly independent, because 0∈S.
In fact, every orthogonal set in R^n without zero vectors is linearly independent. Take a orthogonal set 
and suppose that there are coefficients a_i such that 
. For any i, take the dot product with u_i in both sides of the equation. All product are zero except u_i·u_i=||u_i||. Then 
then 
.
565 is the correct answer
The side length of the square concrete slab if the area is increased by 25% is 5feet
The formula for calculating the area of a square is expressed as:
A = L² where:
L is the side length of the square
Given the area of the square concrete slab = 20 square feet
20 = L²
L =√20
If the area is increased by 25%, new area will be:
An = 20 + (0.25*20)
An = 20 + 5
An = 25 sq.ft
Get the new length
An = Ln²
25 = Ln²
Ln = √25
Ln = 5feet
Hence the side length of the square concrete slab if the area is increased by 25% is 5feet
Learn more here: brainly.com/question/11300671
The tangential line at a certain point is just the derivative so.
. At the point (1,6) we plug the x value in and get the slope at the point (y ' = 2)
The tangential line at that point is
y - 6 = 2(x - 1) (this is the answer)
Maybe try dividing 1092 by 21 I got 52
