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nycguitarguy (previous username: sologuitar) wrote:

Block him, Bob.

Isn't it nice that Bob gives people lots of chances before banning them?

FelizNYC wrote:

Determine if each function is even, odd or neither.

With poly's its really easy: just look at the powers

FelizNYC wrote:

1. g(x) = x^3 - 27x^1

All odd powers -> odd fcn

FelizNYC wrote:

2. f(x) = -x^3 + 12x^1

All odd powers -> odd fcn

FelizNYC wrote:

3. F(x) = -x^4 + 8x^2 + 8x^0

All even powers -> even fcn

FelizNYC wrote:

4. G(x) = -x^4 + 32x^2 + 144x^0

All even powers -> even fcn

FelizNYC wrote:

Given f(x) = -x^3 + 12x, a local maximum value of 16 is said to be at 2.

Determine the local minimum value.

since you can't use calculus then they probably wnat you to look at the picture

install the TI-84 emulator on your phone

plug -x^3+12x into [Y1=]

hit 'graph'

select 'calc'

choose 'minimum'

FelizNYC wrote:

Does the local maximum value of 16 at 2 mean point (2, 16)?

Yeh

FelizNYC wrote:

If so, how does the point (2, 16) help me find the local minimum?

I think youre supposed to assume mirrored symmetry

max at (2,16)

min at (-2,-16)?

this *is* the min but I don't know how you were supposed to know

THis mirroring doesn't always happen so you can't assume

FelizNYC wrote:

Can you post the graph for me?

YOu can do the graph yourself in your phone

Go to Google Play Store

In 'search' box enter 'Graphing calculator plus 84 83'

Install app to get TI-84 emulator on your phone

TI-84 can do things like find the minimum on a graph

(and there's lots of tutorials, how-to's, etc online for Texas Instruments TI-84)

FelizNYC wrote:

What is the purpose of this exercise [other] than algebra practice?

probably no other pt than to give you a chance to

(1) work some more with the fomrulas

(2) get practice seeing when formulas might be useful

FelizNYC wrote:

Verify that the points (0, 0), (a, 0), and (a/2, sqrt{3}a/2) are the vertices of an equilateral triangle. Then show the midpoints of the three sides are the vertices of a second equilateral triangle.

1st part: Equilaterals have all sides the same length

so plug pairs of pts into Distance Formula

2nd part: Use Midpoint Formula to find midpts

Use Distance Formula to show all new sides have same length

FelizNYC wrote:

An equilateral triangle is one in which all three sides are of equal lengths. If two vertices of an equilateral triangle are (0, 4) and (0, 0), find the third vertex. How many of these triangles are possible?

Equilaterals have all sides the same lenbth

Distance Formula:

so sides' lengths is 4

3rd pt will be 4 units from known pts

Both are equal to 4 so set them equal

Square both sides and solve

Now you need to find x

try with (0,0)

this means that there are 2 triangle that work

(draw the dots to see why this is so)

FelizNYC wrote:

Plot the points A = (-1, 8) and M = (2, 3) in the xy-plane. If M is the midpoint of a line segment AB, find the coordinates of B.

just plug into midpoint formjula

Set the x and y coords equal

Solve for x and y

FelizNYC wrote:

Are you saying that the cuberoot{-x} is not -x?

yes I'm saying they're not the same

eg cbrt{8} = 2, not 8

cbrt{27} = 3, not 27

cbrt{-64} = -4, not -64

FelizNYC wrote:

Can you help me with Part B?

find 'v' for part A

plug that into the eqn they gave you

this is all they want for partt B

FelizNYC wrote:

what happend to the cube rt?

FelizNYC wrote:

Can you set up the function for me?

They gave you

They ask if the equation works with

So see if it works

Simplify

does this equal 10?

FelizNYC wrote:

If an object weighs m pounds at sea level, then it's weight W (in pounds) at a height of h miles above sea level is given approximately by W(h) = m[4000/(4000 + h)]^2. If Amy Weighs 120 pounds at sea level, how much will she weigh on Pike's Peak, which is 14,110 feet above sea level?

(dont round until the end!)

FelizNYC wrote:

A. The center of the hoop is 10 feet above the floor and 15 feet in front of the foul line. Determine the initial velocity with which the ball must be shot in order for the ball to go through the hoop.

B. Write a function for the path of the ball using the velocity found in part A above.

C. Determine the height of the 84 after it has traveled 9 feet in front of the basketball.

The only instrutions Im' seeing are the 3 quoted

sorry

Why did original link not work?

Maybe because Imgur doesnt like hotlinking that avoids ads?

but if you right-click (on computer) and pick 'open image in new tab' you get different url

Put that url inside image tags and you get:

domain: They show which bits of x-axis count

range: They show which bits of y-axis count

range: Graph does not go up to y=2

It stops at y=0 (x-axis)

FelizNYC wrote:

How does one use the graph of a function to find the domain and range?

domain: Look at where the graph goes from side to side

Does it quit (like with square roots) or have gaps (like with vert. asymps), or does it go everywhere?

Domain is wherever graph goes along x-axis

(not necessarily right next to the axis but you can trace up or down from the axis to the graph)

range: Look at where the graph goes from bottom to top

Does it quit (like with parabolas) or have gaps (like with hor. asymps), or does it go everywhere?

Range is wherever graph goes along y-axis

(not necessarily right next to the axis but you can trace right or left from the axis to the graph)

FelizNYC wrote:

Given A(x) = 4x•sqrt{1 - x^2}, find the domain of A.

Theres a way to do this so you dont have to try to go from 'x<=1' to '-1<=x<=1'

This gives you two sol'ns: x=1, x=-1

Also you know shape of quadratics like y=x^2-1:

<=0 between sol'ns (when its positive like this)

This lets you go to

FelizNYC wrote:

Try desmos.com or mathway.com for graphing.

YOu can do graphing on your phone

Go to Google Play Store

In 'search' box enter 'Graphing calculator plus 84 83'

Install app to get TI-84 emulator on your phone

TI-84 can do things like find the minimum on a graph

(and there's lots of tutorials, how-to's, etc online for Texas Instruments TI-84)

FelizNYC wrote:

...the path of the ball can be modeled by the function h(x) = -(136x^2)/(v^2) + 2.7x + 3.5, where h is the height of the ball above the floor, x is the forward distance of the ball in front of the foul line, and v is the initial velocity with which the ball is shot in feet per second.

Part B. Write a function for the path of the ball using the velocity found in part A above.

I need help for part B.

Once you get the number for 'v' from part 'A', plug that into the eqn they gave you

(and maybe simplify)

That's all they want for this part

FelizNYC wrote:

Part D. To find additional points, I must create a table in terms if x and h(x).

What were the instructions for this part?

(it's not in your first post, i don't think?)

FelizNYC wrote:

Can you show me STEP BY STEP how to upload photos here using an android phone?

Open google play store

Select 'search'

Enter 'carbon browser'

Select and install

Open carbon brwoser

Enter url for image that you uploaded

Long-press image (hold you finger on the image until a menu pops up)

Select 'open image in new tab'

Go to new tab

Press url box (it should look like i.imgur.io/[bunch of characters].webp?[query string]

note: [bunch of characters] in the new tab will NOT be the same as the [bunch of characters] in the original tab!!!

Select edit (pencil icon)

Erase (back-space) from the end until you get to the .webp

Replace .webp with .jpg

Select 'go' at bottom of keyboard

Your image should disply alone on the page

Copy new url and paste between [ img] [ /img] tags (without the extra spaces of course)

With your image from another thread i got this:

i.imgur.io/7uB3NEl_d.jpg

I removed the '_d' to get i.imgur.io/7uB3NEl.jpg

Putting it between the 'img' tags does this:

if you dont delete the underscore-d then you get a thumbnail (?) thats pretty small:

find where the grpah crosses y-axis: this is y-int

find where the graph crosses x-axis: this is x-int

FelizNYC wrote:

Given f(x) = (x^2 + 2)/(x + 4) and g(x) = 2x/(x - 2), answer the following questions.

A. The point (1, 3/5) lies on the graph of which function?

Plug x=1 into f and g

see which one gives you 3/5 for the answer

FelizNYC wrote:

B. If x = 4, what if g(x)? What point is on the graph of g?

Plug x=4 into g

See what g(4) equals

This is y

Point on g is (4,g(4))

FelizNYC wrote:

C. What is the domain of f and g?

Domains are different for f and g

f: solve x+4=0; everything else is domain

g: solve x-2=0: everything else is domain

FelizNYC wrote:

D. If f(x) = 1/2 and g(x) = 1, what is x for both functions?

f: set (x^2 + 2)/(x + 4) = 1/2 and solve

g: set 2x/(x - 2), = 1 and solve

FelizNYC wrote:

E. Graph the function of f. Graph the function of g.

graph vertical asymptotes

use the rules to find horizontal asymptotes

plot intercepts

make T-chart

graph a bunch of other points

then draw graph

FelizNYC wrote:

F. What is the range of f? What is the range of g?

like Bob said: look at the graph for the range

(you already have the domains)

FelizNYC wrote:

G. List the x and y intercepts, if any, of the graph of f and graph of g.

y-int: set x=0 and solve

x-int: set y=0 and solve

FelizNYC wrote:

H. Find f(a + b) and g(a - b).

plug a+b in for each x in f

plug a-b in for each x in g

simplify if you can

FelizNYC wrote:

Given a graph, how does one determine if it is a function using the vertical line test?

see if there is anywhere you could draw a vertical line and cross the graph more than 1 time

If yes, then not a fcn

FelizNYC wrote:

A function has the following points:

(-6, -3), (-5, -2), (-3, 0), (0, 3), (2, 4), (4, 3), (6, 0), (8, -2), (10, 0), (11, 1)

A. Find f(0) and f(-6)

f(0) comes from pt (0,3)

f(-6) comes from pt (-6,-3)

FelizNYC wrote:

B. If f(3) positive or negative?

none of the pts has x=3

maybe f(-3)?

then use pt (-3,0)

FelizNYC wrote:

C. For what values of x is f(x) = 0?

f=0 comes from pts (-3,0),(6,0),(10,0)

FelizNYC wrote:

D. For what values of x is f(x) > 0?

f>0 comes from pts (0,3),(2,4),(4,3),(11,1)

FelizNYC wrote:

E. List the x and y intercepts.

use defs:

x-int: y=0, so pts (-3,0),(6,0)(10,0)

y-int: x=0, so pt (0,3)

FelizNYC wrote:

How does one use the graph of a function to find any symmetry with respect to the x-axis, y-axis, or origin?

Use def. of the symmetries

even: mirrored on each side of y-axis (like y=x^2)

odd: mirrored but upside down on other side of y-axis (like y=x^3)

origin: each pt matches another pt on th e other side of the origin (like y=x^3)