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## #1 Help Me ! » Complex Numbers » 2014-03-09 07:51:51

MERTICH
Replies: 1

If a  and b  are real numbers such that (a-ib)^2 =4,

verify that

a^4 +a^2 -16 =0

## #2 Re: Help Me ! » I Ca'nt Figure Out If This Is An Exponential Question » 2013-12-28 07:18:20

Thank you guys! I really appreciate

## #3 Re: Help Me ! » I Ca'nt Figure Out If This Is An Exponential Question » 2013-12-28 06:57:29

bob bundy wrote:

That's not the way to show the function for A.  But no matter; we have enough information to answer the question.

(i) List the start values.

(ii) Identify the growth rates.  We don't have to find a function for B and as it is decreasing we can dismiss it for the question.

(iii) Choose a starting value and growth rate to suit D.  It looks like many answers are possible.

Bob

edit.  I think this is really just a question about functions and graphs.  The 'stock rates' is just window dressing.

22<Dstartprice<25, and it's difficult to figure out the growth rate for B, though I can tell that stock fell by 44c, then 43c, may be 42, 42......

## #4 Re: Help Me ! » I Ca'nt Figure Out If This Is An Exponential Question » 2013-12-28 06:38:39

bob bundy wrote:

Bob

ps.  there are 4 stock functions.  The function for D is governed by the statement

It should have the second lowest starting price and the second highest rate of growth. Using complete sentences, justify that your function meets these requirements.

The  Price for Stock A is given by the function y= 25(1.08)x, where x is the number of days, 1.08 the rate of growth, and 25 the start price

## #5 Re: Help Me ! » I Ca'nt Figure Out If This Is An Exponential Question » 2013-12-28 06:21:21

A ,B and C are separate kinds of stocks with different prices. That is the way I see it. Now THEY WANT STOCK D .

## #6 Re: Help Me ! » I Ca'nt Figure Out If This Is An Exponential Question » 2013-12-28 06:13:00

bobbym wrote:

Hi;

Neither of those equations fits the data you are given.

So how should I go about it, pliz help..

## #7 Re: Help Me ! » I Ca'nt Figure Out If This Is An Exponential Question » 2013-12-28 05:45:39

y(t) = a × ekt :

SO SHOULD THE FUNCTION BE    y=30 x e^1.2x,

where 30 is the start price, and 1.2 is 0.4 % of \$30, and x number of days?

OR,  y = 30 + 1.2x

## #8 Help Me ! » I Ca'nt Figure Out If This Is An Exponential Question » 2013-12-28 05:39:36

MERTICH
Replies: 14

Gordon is evaluating some stocks he wants to purchase. You can see the function of the stock price below. The variable x represents days.

Stock
A: f(x) = 25(1.08)x
B: x    f(x)
0    22.00
1    21.56
2    21.13
C: The initial price of this stock is \$30, but it has been increasing 4% each day.

1.) Create the price function for Stock D. It should have the second lowest starting price and the second highest rate of growth. Using complete sentences, justify that your function meets these requirements.
2.) Graph the price function for Stock D. Explain the key features of the graph wit

## #9 Re: Help Me ! » Squeeze Theorem » 2013-12-18 04:02:47

that is to say the denominator power of both bounds is greater than the numerator power, such that when x approaches infinity, f(x) becomes zero.....thank you guys!

## #10 Re: Help Me ! » Squeeze Theorem » 2013-12-18 02:29:37

yes, but then how do you fit in the rest of the equation, or is it 2/( x^2 +2) </= f(x) </= 4/ (x^2 +2)  ?

## #11 Re: Help Me ! » Squeeze Theorem » 2013-12-18 02:03:29

@ zetfunc , you mean like, since I know that no matter what, -1<sinx < 1 , so I should subsititute sin(e^x) with 1 and -1, in the expression to get my lower and upper bound?

## #12 Re: Help Me ! » Squeeze Theorem » 2013-12-18 01:48:31

I would also appreciate a stage by stage go...

## #13 Help Me ! » Squeeze Theorem » 2013-12-18 01:42:00

MERTICH
Replies: 8

Use the squeeze theorem to determine

LIM                                [ 3 -sin(e^x)]/                 3 minus Sin(exp x) divided by
x--> infinity                     [V (X^2 + 2)]                   square root of ( x squared + 2)

## #14 Re: Help Me ! » Systems Of Linear Equations » 2013-12-01 21:03:20

Thank you guys, I thought as much, but you know, when doing it alone you doubt yourself. I have learnt something today : a system with three variables and two equations will NOT yield precise values for the variables, except by inserting the infinite number of all possible solutions. Thanx. Will be back soon.

## #15 Re: Help Me ! » Systems Of Linear Equations » 2013-12-01 18:16:30

bobbym wrote:

Hi MERTICH;

Best you can do is solve it in terms of x or any of the other 2 variables.

Now substituting any value into x will yield a solution to the system.

I am so sorry Bobbym . The other z is positive.

It should be:

5x+2y-z =9
4x-2y+z =0

## #16 Re: Help Me ! » Systems Of Linear Equations » 2013-12-01 18:13:05

Nehushtan wrote:

You made a mistake. It should be

Since there are three variables and only two equations, there will be infinitely many solutions.

I have edited the system. the other z is positive. Sorry guys.

it should be

5x+2y-z = 9

4x-2y+z =0

## #17 Help Me ! » Systems Of Linear Equations » 2013-12-01 09:32:10

MERTICH
Replies: 8

5x  +2y  - z =9
4x  - 2y  +z  =0

I have soved this problem to the point of getting that :

9x  =  9
and thus,   x    =  1.

How do I solve for y and z. Am in College.