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thrustfault
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Let f(x) = sin(x) + icos(x). Show that f(x) = 1.
I'm not even sure where to start here...
 one year ago
 one year ago
thrustfault Group Title
Let f(x) = sin(x) + icos(x). Show that f(x) = 1. I'm not even sure where to start here...
 one year ago
 one year ago

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khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
hey its too much easy... f(x)=sqrt((1)^2+(1)^2)=sqrt(2)
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
here we will take its real part 1 will cos(x) and also 1 from imagnary part i(sinx) hey u have written wrong equation.. its cos(x)isin(x)
 one year ago

thrustfault Group TitleBest ResponseYou've already chosen the best response.0
The question is right. I know DeMoivres, but in this case it's sin(x) + icos(x).
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
ah oookkk ya its absolute value
 one year ago

thrustfault Group TitleBest ResponseYou've already chosen the best response.0
So far I have LHS = \[\frac{ e ^{ix}e^{ix} }{ 2 } + \frac{ e ^{ix}+e^{ix} }{ 2 }i\] Have I completely overthought the problem ? :)
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
no i is denominator from demorvie`s, but in this case I did`nt get u how u got this result
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
ok am gonna solve its prove and implement according to this condition the `ll msg u here ok
 one year ago

thrustfault Group TitleBest ResponseYou've already chosen the best response.0
Thanks :) I'm so confused...
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
hahahhah i just wanna say write i in denominator ok i mean (eix−e−ix)2+(eix+e−ix)2i
 one year ago

thrustfault Group TitleBest ResponseYou've already chosen the best response.0
Hmm... I don't get it. How does that show that sin(x) + icos(x) = 1?
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
oh i see wait i solve it and post the diagrame okk buddy
 one year ago

thrustfault Group TitleBest ResponseYou've already chosen the best response.0
Anyone?
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
daer i can`t .. i have seen the same result for it sqareroot 2 iz answer for both condition.. cos when we see cosx+isinx,, or sinx+icosx... taking coifficients we get the same result..
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
i thinks its wrong question or some thing missing ... can u give the link where did u got it from ???
 one year ago

thrustfault Group TitleBest ResponseYou've already chosen the best response.0
Yep, it's question 1 iv) from this paper: http://www.scribd.com/doc/112148611/MATH1131Mathematics1A1 Thanks :)
 one year ago

thrustfault Group TitleBest ResponseYou've already chosen the best response.0
pdf attached here.
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
http://www.mathwarehouse.com/ellipse/equationofellipse.php http://www.algebra.com/algebra/homework/equations/THEO20100329.lesson
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
u got ur answer or not /??
 one year ago

thrustfault Group TitleBest ResponseYou've already chosen the best response.0
Nope, heh. Not yet :(
 one year ago

khurramshahzad Group TitleBest ResponseYou've already chosen the best response.0
ok if its difficault then msg me ur question i will solve it my self and will post the pic here ok
 one year ago

thrustfault Group TitleBest ResponseYou've already chosen the best response.0
Yeah I don't know how to get the function to = 1...
 one year ago

AccessDenied Group TitleBest ResponseYou've already chosen the best response.1
I am thinking that you are using the fact that f(x) represents the exact distance between it and 0 on the complex plane... Notice that you can create a right triangle with the real part of f(x) and the imaginary part of x on a complex plane: dw:1352104120632:dw So, here, Re(f) = sin(x) and Im(f) = cos(x). We drop off the i since we're dealing with distances only for the imaginary part. Using Pythagorean theorem, f(x)^2 = (Re(f))^2 + (Im(f))^2 = sin^2 x + cos^2 x. Since we have a neat trigonometric identity here, we can use it to reduce sin^2 x + cos^2 x as 1. Take the square root of both sides and we're done. :)
 one year ago

thrustfault Group TitleBest ResponseYou've already chosen the best response.0
Thanks so much for your clear and concise answer!! I've been stuck on this question for a long time :)
 one year ago

AccessDenied Group TitleBest ResponseYou've already chosen the best response.1
You're welcome! :)
 one year ago

sirm3d Group TitleBest ResponseYou've already chosen the best response.1
perhaps this definition can refresh you \[\huge \left a + bi \right=a^2+b^2 \]
 one year ago
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