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
.
Answer:
√(110 - n)
Step-by-step explanation:
This can't be simplified. All we can do here is re-write "square root of 110 - n" symbolically, which comes out to √(110 - n). The parentheses are essential for clarity.
Answer:
The base is: ![3 \sqrt[3]{4}](https://tex.z-dn.net/?f=3%20%5Csqrt%5B3%5D%7B4%7D)
Step-by-step explanation:
Given
![f(x) = \frac{1}{4}(\sqrt[3]{108})^x](https://tex.z-dn.net/?f=f%28x%29%20%3D%20%5Cfrac%7B1%7D%7B4%7D%28%5Csqrt%5B3%5D%7B108%7D%29%5Ex)
Required
The base
Expand 108
![f(x) = \frac{1}{4}(\sqrt[3]{3^3 * 4})^x](https://tex.z-dn.net/?f=f%28x%29%20%3D%20%5Cfrac%7B1%7D%7B4%7D%28%5Csqrt%5B3%5D%7B3%5E3%20%2A%204%7D%29%5Ex)
Rewrite the exponent as:

Expand


Rewrite as:
![f(x) = \frac{1}{4}(3 \sqrt[3]{4})^x](https://tex.z-dn.net/?f=f%28x%29%20%3D%20%5Cfrac%7B1%7D%7B4%7D%283%20%5Csqrt%5B3%5D%7B4%7D%29%5Ex)
An exponential function has the following form:

Where

By comparison:
![b =3 \sqrt[3]{4}](https://tex.z-dn.net/?f=b%20%3D3%20%5Csqrt%5B3%5D%7B4%7D)
So, the base is: ![3 \sqrt[3]{4}](https://tex.z-dn.net/?f=3%20%5Csqrt%5B3%5D%7B4%7D)
Answer:
The price of 1 adult ticket is $ 11 and price of 1 child ticket is $13
Step-by-step explanation:
Let x be the cost of 1 adult ticket
Let y be the cost of 1 child ticket
Cost of 8 adult tickets = 8x
Cost of 9 child tickets = 9y
We are given that A local kids play sold 8 adult tickets and 9 child tickets for a total of $205
So, 8x+9y=205 ----- 1
Cost of 4 adult tickets = 4x
Cost of 3 child tickets = 3y
We are given that 4 adult tickets and 3 child tickets for a total of $83.
4x+3y=83 ----2
Plot 1 and 2 on graph
8x+9y=205 -- Red line
4x+3y=83 -- Blue line
Intersection point provides the solution
So, Intersection point =(11,13)
So, The price of 1 adult ticket is $ 11 and price of 1 child ticket is $13
X= 40 is the answer to this equation