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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
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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khurramshahzadBest 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

khurramshahzadBest 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

thrustfaultBest 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

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

thrustfaultBest 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

khurramshahzadBest 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

khurramshahzadBest 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

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

khurramshahzadBest 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

thrustfaultBest 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

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

khurramshahzadBest 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

khurramshahzadBest 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

thrustfaultBest 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

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

khurramshahzadBest 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

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

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

khurramshahzadBest 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

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

AccessDeniedBest 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

thrustfaultBest 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

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

sirm3dBest 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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