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#26 Re: Help Me ! » Inequality » 2010-12-08 19:18:52

my friend i check ans is squt5
this is "AIEEE" 2007 question

#27 Re: Help Me ! » Inequality » 2010-12-08 19:14:43

friend bobby ask good question of maxima $minima
tell me about true answer

#29 Re: Help Me ! » Inequality » 2010-12-08 19:06:06

x+y-z=0  ;
z=x+y;
Max(3x-y-3z);
put the valu of z
Max(-4y)=.........(d)
x^2+ 2y^2=1............(A)
lets assume trigonometric variable which setisfied (A)
x=sin(k),z=cos(t)/squt(2);
y=[cos(t)/squt(2)  -sin(t)];
From (d)
Max(-4y)=max (4sin(t)-2*squt(2)cos(t));
solve like previous question
obtain squt(24),
"TELL ME FRIEND about process ans may be wrong due to calculation mistake"

#30 Re: Help Me ! » Inequality » 2010-12-08 18:40:03

why all of you are going so large my friend
x^2+y^2=1
let x=sin(a);
y=cos(a);
x+2y=sin(a)+2cos(a)=squt(5)sin(a+t);
hence maximum valu=squt(5), where t=tan^-1(2)

#31 Re: Help Me ! » Inequality » 2010-12-08 18:31:00

in such type of problem of inequality i.e
A.M>=G.M
maxima $ minima exist at point where equality will hold i.e "if x=y=z"
you can assume x=y=z=k;
given that x+y+z=1
hence 3k=1
k=1/3
put the valu $obtain the answer
my friend this trick is quite comfortable if you are preparing for "I.I.T"

#32 Re: Help Me ! » Multivariable Differentiation » 2010-11-19 18:34:44

hello my friend in my openion arctan(x)=tan^-1(x)
tan inverse x
above function can be written as arctan[2(y/x)/(1-y^2/x^2)]
now let y/x=tanb
F(x)=arctan[2tanb/(1-tan^ 2b)]
F(x)=arctan[tan2b]
F(x)=2b
F(x)'=2*b'
where b=tan inverse y/x

#33 Re: Help Me ! » Co-ordinate Geometry » 2010-11-19 18:14:57

hello bob you are absolutely wrong

to diffrentiate acute obtuse angle bisector take one line and one bisector

"LET tan(x) is angle between one line and one bisector if [tan(x)<=1]then bisector is acute angle opther wise obtuse angle bisector"

#34 Re: Exercises » Challenge » 2010-11-19 17:40:15

hello friend in my openion you are wrong in frist question

#35 Re: Help Me ! » provement » 2010-10-24 22:53:06

who will responsible for genration of trigonometry
please tell me about initial steps am not test you friend actually i want to know
because i want to work on this field

ALSO WRITE MATHMATICAL STEPS OF "GENRATION"

#36 Re: Help Me ! » provement » 2010-10-24 22:46:07

hiiii friends please try to ans a ques.
if X=0+i;
then what is valu of log(X)
where i represents a complex number

#37 Re: Help Me ! » more trigonmetry » 2010-09-24 17:30:25

hi my friend cosx-2sinx cosx/cos^2x-sin^2x+sinx-1
cosx(1-2sinx)/(-sin^2x-(1-cos^2x)+sinx)
cosx(1-2sinx)/sinx(1-2sinx)   {wherex!=n *pi}
=cotx

#38 Re: Help Me ! » trig identities » 2010-09-24 17:15:29

hi kfarnan i think at  valu of   x where cos x & cot x =0 then that enequality will't valid
if valid then
{sec^2x-tan^2x}=1,proved

#39 Re: Help Me ! » Solving Logarithmic Inequalities With a Base That Is 0<x<1 » 2010-09-24 17:01:53

dear friend anakin in my openion you do mistake in inquality
~if log b (a)>c
if base of log is {.}
then inequality will change
if>=1 then as it remain

#40 Re: Exercises » cos(x - y) » 2010-09-16 22:54:26

hello JaneFairfax i think that you are intresested in trigo.
but i challange you in trigo. calculus algebra. coordinate pleaseeeeeeeee
accept my challenge and ask question from me

#41 Re: Help Me ! » What is second partial derivative? » 2010-09-14 01:59:12

second partial derivative of a given function Y=F(x) exist if there will be no sharp turn in the graph of F'(x)
let y=f(x,z)
then y'=f(x+h,z)-f(x,z)/h when lim'h'tends to 0 is partial derivative because x is variable
similerly find derivative of y treating z as variable because of

derivative is limiting process so for y'' repeat above process

#42 Re: Help Me ! » provement » 2010-09-14 01:37:13

what is range of 1/(3-5cosx)

#43 Re: Dark Discussions at Cafe Infinity » Debate #001: Is math a science? » 2010-09-08 00:31:37

my openion about this is
Mathmatics is the   perfect science

#44 Re: Help Me ! » provement » 2010-09-07 01:44:08

friend i ask one question related to range yesterday very intresting
try to solve it

#45 Re: Help Me ! » provement » 2010-09-07 01:39:40

2 or 3 days before i ask a problem what is eaist way to find area of triangle i given sides as 1-(x)^1/2 ,5-(x)^1/2 ,7-(x)^1/2 friend all of you not thing about question
here triangle will not be form
triangle will form if (sum of smallest side )>=biggest side

#46 Re: Help Me ! » provement » 2010-09-07 01:30:47

my friends i want to help
all of you know that
A=abc/4R
hence 4RA=abc
A.M>=G.M
(a+b+c )/3>=(abc)^1/3
now put the valu of abc=4RA
hence you can get the answer

#47 Re: Help Me ! » provement » 2010-09-07 01:23:16

if you want solution of sin30=1/2 then search on google
"why sin30=1/2" am allready given solution on that

#48 Re: Help Me ! » provement » 2010-09-07 01:07:48

if a,b,c are sides of a triangle & A be the area of triangle R will be radius of
circumcircle of that triangle
p.t (a+b+c)>=3{4RA}^1/3

#49 Re: Help Me ! » provement » 2010-09-06 01:35:43

if A is area of triangle &a,b,c are sides & R is radius of circumcircle which circumscribed the triangle

then prove that (a+b+c)>=3(4RA)^1/3

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