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kaylalynn
Which of the following functions is not a sinusoid? y = sin x y= Sqrtx y = cos x None of the above are sinusoids.
definitely \[\sqrt x\] is not a sinusoid , it doesn't vary as a sine wave or a cosine wave
thats what i was thinkging thanks!!
btw does a sinusoid have to go below the x axis??
no, sinusoid wave are those which show a smooth repetitive variation or oscillation , like a sine wave or a cosine wave , it doesn't have to go below x axis, if you shift the origin up with respect to the original origin you wont have it below x axis, its just a general trend
|dw:1369863941221:dw| O new is the new origin
I would say yes (it has to go below), since I take as definition that a sinusoid is a function of the form \(\lambda \sin(\alpha x + \phi)\), with \(\lambda, \alpha, \phi\in\mathbb R\). But you allow a vertical translation in your definition the answer is yes..
you have to find in your definition in your course. (wikipedia says that the general form allows for a vertical shift). If your definition is the general definition, then there are two sinusoid curves on this picture.