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#1 Re: Help Me ! » Helpi with finding the inverse of an exponential function » 2011-01-09 06:35:14
Lol, "This is so corny and pompous, I just have to say it" That made me think u were lyk a 50 year old guy whu had nuthing to do so he was spending time on math forums and just got pissed cuz of my "vorny" question!:P
Yup. I'm a student, and lyk u can see a pretty horrible one :$
#2 Re: Help Me ! » Helpi with finding the inverse of an exponential function » 2011-01-09 06:32:42
Um sorry but I dont get wht u did after u got the quadratic equation u=(√y^2+1)+y! I mean the last 3 steps. Cud u please explain!
#3 Re: Help Me ! » Helpi with finding the inverse of an exponential function » 2011-01-09 06:19:34
Thanx guys. bobbym u truly are a genius! If u dont mind me asking r u a student?
#4 Re: Help Me ! » Helpi with finding the inverse of an exponential function » 2011-01-09 03:01:50
Um I need to find th inverse using the function given above!
#5 Help Me ! » Helpi with finding the inverse of an exponential function » 2011-01-09 00:17:34
- aisha00
- Replies: 10
Find the inverse of the following:-
1)f(x)= (e^x)-(e^-x)/2
The first step I did is to interchange the x and y, then i moved the 2
2x=(e^y)-(e^-y)
Then i find a common factor
2x=e^-y(e^2y-1)
I dunno wht to do after this! The answer for the question is ln(x+√x^2+1)
Thanx 
#6 Re: Help Me ! » Standard normal distribution Question. » 2011-01-04 05:42:08
Ok now im confused, doesnt the z value i got(-0.25)correspond to the 63 ?
#7 Help Me ! » Standard normal distribution Question. » 2011-01-04 03:27:13
- aisha00
- Replies: 3
The speed limit on Interstate 75 around Findlay, Ohio, is 65 mph. On a clear day with no construction, the mean speed of automobiles was measured at 63 mph with a standard deviation of 8 mph. If the speeds are normally distributed, what percentage of the automobiles is exceeding the limit?
The first step i did was (63-65/8)=-0.25
From the table the value i get for -0.25 is 0.4013
If i subtract 0.4013 from 1 I get the percentage of automobiles exceeding 63, whereas the question asks for the percentage of vehicles exceeding 65, so how do i find that!
#8 Help Me ! » Urgent help with cofunction identities » 2010-12-27 00:52:04
- aisha00
- Replies: 2
Hi people. I was doin the identities chapter and im pretty much done with it except for the following, im kinda stuck with it cuz i hav no solved examples tht show how these q's r dun.
Verify the following identity
1)Cos(x-3pi/2)= -sinx
Simplify
1)Sin(x+9pi/2)
The answer is cos x
P.S-Please mention all the steps as im quite a beginner at this. Thankyou
#9 Re: Help Me ! » Help with web graphing calculator » 2010-12-15 01:10:15
Hahaha i feel dumb, thanx though
#10 Re: Help Me ! » Help with web graphing calculator » 2010-12-14 23:09:10
Ok so i tried tracing points using the calci 2 which i've posted the link. But i just get the origin points (0,0). I tried using diff types of graph but everytym i just get dose 2 points 
#11 Re: Help Me ! » Help with web graphing calculator » 2010-12-14 04:01:30
Find some pair points on your functions and an explanation on how you trace the function and how to find any value for y for specific values for x.
Thats a question from the project tht im doing. Can u please tell me wht tracing the function means? I'm sorry for bothering u but im really clueless here.
#12 Re: Help Me ! » Help with web graphing calculator » 2010-12-14 03:52:51
But why do i only get the graph starting from 0 to positive inifnity? Like the range is either greater than or equal to zero from the graph i get, BUT the buk says its all real numbers!
#13 Re: Help Me ! » Help with web graphing calculator » 2010-12-14 02:16:04
Yup i got it, thanx . And do u know how to find the cube root of x ? theres only square root given in this one. Even if u knw it on sum othr web calci its fine, lemme knw. Thanx a ton
#14 Help Me ! » Help with web graphing calculator » 2010-12-14 00:54:04
- aisha00
- Replies: 10
Hi. I'm using a web graphing calculator and im very new to the graphing calculator so i'd appreciate it if sum1 cud temme how to get a horizintal shift on it. I tried doing y = (x^2+2) but it gives me vertical shift not horizontal. Can any1 temme whr im going wrong, I hav a project due tomorrow so please reply. Thankyou:).
P.S- This is the link to the calculator im using!
http://my.hrw.com/math06_07/nsmedia/tools/Graph_Calculator/graphCalc.html
#15 Re: Help Me ! » Help with probability! » 2010-12-10 03:31:32
Thanx
5) There are 5! = 5*4*3*2*1 = 120 ways to arrange the washers. Two of these ways will be in size order (smallest to largest, and largest to smallest). So the answer is 2/120 = 1/60.
#16 Re: Help Me ! » Help with probability! » 2010-12-10 03:29:04
I know its correct, i just dunno how they got it ? Thanx
Hi aisha00;
Welcome to the forum!
6) The answer is 8 / 11 so .727 is correct.
#17 Help Me ! » Help with probability! » 2010-12-10 00:48:01
- aisha00
- Replies: 36
I hav an exam on Sunday, and while studyin for it I came across a few questions that i cudn't solve. I'd be grateful if sum1 could help me wid them. Thank you.
5)Find the probability that if 5 different-sized washers are arranged in a row, they will be arranged in order of size
The answer is 1/60
6)All holy plants are dioecious-a male plant must be planted within 30 to 40 feet of the female plant in order to yield barriers. A home improvement store has 12 unmarked holly plants for sale, 8 of which are female. If a homeowner buys 3 plants at random, what is the probability that berries will be produced?
The answer is 0.727.
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