Author Topic: Additional Math Help HERE ONLY...!  (Read 65126 times)

Offline astarmathsandphysics

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Re: Additional Math Help HERE ONLY...!
« Reply #90 on: June 02, 2009, 03:42:42 pm »
HOW do u get y
   3^2y +5(3^y-10)=0

sub p=3^y to get p2+5(p-10)=0 so p2+5p-50=(p+10)(p-5)=0 so p=-10 or 5 so y=(logp)/log3 =(log-10)/log3 impossible since log-10 does not exist or y=(log5)/log3
« Last Edit: June 02, 2009, 03:44:14 pm by astarmathsandphysics »

Offline shan2391

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Re: Additional Math Help HERE ONLY...!
« Reply #91 on: June 02, 2009, 04:39:11 pm »
Thanks astar :)
By the way i was reading the syllabus n did not find velcity n relative velocity in it

Offline sweetsh

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Re: Additional Math Help HERE ONLY...!
« Reply #92 on: June 02, 2009, 04:43:59 pm »
3(sinx-cosx)=2(sinx+cosx)

?

Offline sweetsh

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Re: Additional Math Help HERE ONLY...!
« Reply #93 on: June 02, 2009, 05:04:10 pm »
PLease answer

Offline shan2391

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Re: Additional Math Help HERE ONLY...!
« Reply #94 on: June 02, 2009, 05:09:59 pm »
3sinx-3cosx=2sinx+2cosx
sinx=5cosx
sinx/cosx=5
tanx=5
x=78.69

Offline sweetsh

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Re: Additional Math Help HERE ONLY...!
« Reply #95 on: June 02, 2009, 05:13:39 pm »
Thank youuuuu

Offline moraesikae

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Re: Additional Math Help HERE ONLY...!
« Reply #96 on: June 02, 2009, 05:16:03 pm »
3sinx-3cosx=2sinx+2cosx
sinx=5cosx
sinx/cosx=5
tanx=5
x=78.69
there is more to it,,,it could be either 78.89 or 256.7

Offline shan2391

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Re: Additional Math Help HERE ONLY...!
« Reply #97 on: June 02, 2009, 05:17:29 pm »
GUys can any 1 help me with how to find domain and range of functions

Offline moraesikae

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Re: Additional Math Help HERE ONLY...!
« Reply #98 on: June 02, 2009, 05:18:56 pm »
3sinx-3cosx=2sinx+2cosx
sinx=5cosx
sinx/cosx=5
tanx=5
x=78.69
there is more to it,,,it could be either 78.89 or 256.7
sorry i mean 78.69.

Offline moraesikae

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Re: Additional Math Help HERE ONLY...!
« Reply #99 on: June 02, 2009, 05:19:31 pm »
GUys can any 1 help me with how to find domain and range of functions

read previous pages.. it's all there :)

Offline Sweet_03

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Re: Additional Math Help HERE ONLY...!
« Reply #100 on: June 02, 2009, 05:22:45 pm »
Thaaaank You Very Much

Offline ramezamgad

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Re: Additional Math Help HERE ONLY...!
« Reply #101 on: June 02, 2009, 05:46:35 pm »
3sinx-3cosx=2sinx+2cosx
sinx=5cosx
sinx/cosx=5
tanx=5
x=78.69
there is more to it,,,it could be either 78.89 or 256.7
sorry i mean 78.69.
hey sweetsh
the method is correct but after obtaining the eq tanx=5 u should see the range of values of x written in the quest. it is generally 0<x<360
so u have to think when tanx is +ve and tan is +ve in the 1st and 3rd quadrats (ASTC rule)
so after getting x of the 1st quadrat u calculate the other value in the 3rd quadrat which is 180+x
finally x={78.7,258.7}
« Last Edit: June 02, 2009, 05:48:42 pm by ramezamgad »

Offline shan2391

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Re: Additional Math Help HERE ONLY...!
« Reply #102 on: June 02, 2009, 06:10:11 pm »
hey can any1 giv me a breif about how to find range & domain of a function.
AM really struggling wid this

Offline ramezamgad

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Re: Additional Math Help HERE ONLY...!
« Reply #103 on: June 02, 2009, 06:38:31 pm »
for a linear function u must have either the domain or the range and use it to find the other
the domain is the values of x and they produce values of y called the range

eg  find the range for the eq. f(x)=y=3x+1   0=<x<5
y=1 at x=0       y=16 at x=5
so 1=<f(x)<16

quadratic functions:
the previous method cannot be used because it is in a shape of a curve and it has a max or min value

eg f(x)=y=x^2  + 2          -2<x<4

if u solve it in the prev. method ----> y=6    y=18  and will consequently write that 6<f(x)<18 which is not right

u have to determine the turning point of the curve
the most straightforward method is to find dy/dx and equating it to 0 which will give u the value of x to get the max. or min point
in the example dy/dx=2x
0=2x -----> x=0
y=2 at x=0        therefore the right range is 2=<f(x)<18

hope u find that useful

Offline vanibharutham

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Re: Additional Math Help HERE ONLY...!
« Reply #104 on: June 02, 2009, 07:43:16 pm »
Any other last minute queries?
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