- #1
amcavoy
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2nd Order ODE
y''+y=0
I come up with the solutions of y1=c1eix, y2=c2e-ix. Now, using these I try to find the cooresponding real-valued solutions:
eix=cos(x)+isin(x)
e-ix=cos(x)-isin(x)
Both of which have real-valued solutions cos(x). However, when I looked this up online, Wikipedia stated that the answer was y=c1sin(x)+c2cos(x). Am I doing something wrong here? Thanks.
y''+y=0
I come up with the solutions of y1=c1eix, y2=c2e-ix. Now, using these I try to find the cooresponding real-valued solutions:
eix=cos(x)+isin(x)
e-ix=cos(x)-isin(x)
Both of which have real-valued solutions cos(x). However, when I looked this up online, Wikipedia stated that the answer was y=c1sin(x)+c2cos(x). Am I doing something wrong here? Thanks.
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