What are the dimensions of the poster at 1/2 it’s current size

Change each of the following points from rectangular coordinates to spherical coordinates and to cylindrical coordinates.

FromTheMoon [43]

Answer and Step-by-step explanation: Spherical coordinate describes a location of a point in space: one distance (ρ) and two angles (Ф,θ).To transform cartesian coordinates into spherical coordinates:

$\rho = \sqrt{x^{2}+y^{2}+z^{2}}$

$\phi = cos^{-1}\frac{z}{\rho}$

For angle θ:

If x > 0 and y > 0: $\theta = tan^{-1}\frac{y}{x}$ ;

If x < 0: $\theta = \pi + tan^{-1}\frac{y}{x}$ ;
If x > 0 and y < 0: $\theta = 2\pi + tan^{-1}\frac{y}{x}$ ;

Calculating:

a) (4,2,-4)

$\rho = \sqrt{4^{2}+2^{2}+(-4)^{2}}$ = 6

$\phi = cos^{-1}(\frac{-4}{6})$

$\phi = cos^{-1}(\frac{-2}{3})$

For θ, choose 1st option:

$\theta = tan^{-1}(\frac{2}{4})$

$\theta = tan^{-1}(\frac{1}{2})$

b) (0,8,15)

$\rho = \sqrt{0^{2}+8^{2}+(15)^{2}}$ = 17

$\phi = cos^{-1}(\frac{15}{17})$

$\theta = tan^{-1}\frac{y}{x}$

The angle θ gives a tangent that doesn't exist. Analysing table of sine, cosine and tangent: θ = $\frac{\pi}{2}$

c) (√2,1,1)

$\rho = \sqrt{(\sqrt{2} )^{2}+1^{2}+1^{2}}$ = 2

$\phi = cos^{-1}(\frac{1}{2})$

$\phi$ = $\frac{\pi}{3}$

$\theta = tan^{-1}\frac{1}{\sqrt{2} }$

d) (−2√3,−2,3)

$\rho = \sqrt{(-2\sqrt{3} )^{2}+(-2)^{2}+3^{2}}$ = 5

$\phi = cos^{-1}(\frac{3}{5})$

Since x < 0, use 2nd option:

$\theta = \pi + tan^{-1}\frac{1}{\sqrt{3} }$

$\theta = \pi + \frac{\pi}{6}$

$\theta = \frac{7\pi}{6}$

Cilindrical coordinate describes a 3 dimension space: 2 distances (r and z) and 1 angle (θ). To express cartesian coordinates into cilindrical:

$r=\sqrt{x^{2}+y^{2}}$

Angle θ is the same as spherical coordinate;

z = z

Calculating:

a) (4,2,-4)

$r=\sqrt{4^{2}+2^{2}}$ = $\sqrt{20}$

$\theta = tan^{-1}\frac{1}{2}$

z = -4

b) (0, 8, 15)

$r=\sqrt{0^{2}+8^{2}}$ = 8

$\theta = \frac{\pi}{2}$

z = 15

c) (√2,1,1)

$r=\sqrt{(\sqrt{2} )^{2}+1^{2}}$ = $\sqrt{3}$

$\theta = \frac{\pi}{3}$

z = 1

d) (−2√3,−2,3)

$r=\sqrt{(-2\sqrt{3} )^{2}+(-2)^{2}}$ = 4

$\theta = \frac{7\pi}{6}$

z = 3

5 0

3 years ago

Which of these systems has one unique solution?

Shtirlitz [24]

Answer:

D

Step-by-step explanation:

A,B,and C can not solve. because they have wrong answers.

6 0

3 years ago

Tom baked 14 cookies with 2 scoops of flour with 11 scoops of flour how many cookies can tom bake

vodomira [7]

Answer:77

Step-by-step explanation:

4 0

3 years ago

Erin makes a paper chain. Each loop of the paper chain is about 3 inches long. Erin puts 8 loops of paper together. About how lo

prohojiy [21]

For eight loop, multiply it by 3 to get the whole length of loop
8 x 3 = 24 inches
Since 12 inches is equivalent to 1 feet, convert that
24 inches * (1 feet / 12 inches) = 2 feet

5 0

3 years ago

Jane is trying to estimate the average electric bill amount of people who live in Las Cruces in summer time. She randomly select

Lina20 [59]

Answer:

The estimated average electric cost amount of all residents in Las Cruces = 182.9

Step-by-step explanation:

The bill amounts from the electric company for the month of July for 10 randomly selected houses from the map was obtained to be

135 265 215 103 156 203 125 156 230 241

Using the Central Limit theory, the mean of a sample extracted randomly from an independent distribution is approximately equal to the population mean of the independent distribution.

This means that the sample mean of a random sample extracted from the population is a good estimate of the population mean.

Sample mean ≈ Population mean

μₓ = μ

Mean = = (Σx)/N

The mean is the sum of variables divided by the number of variables

x = each variable

N = Sample size = 10

Σx = (135+265+215+103+156+203+125+156+230+241) = 1,829

Sample mean = (1,829/10) = 182.9

Population mean ≈ sample mean

Population mean ≈ 182.9

Hope this Helps!!!

8 0

3 years ago