Contsruct a graph after finding the following: A:Domain B:X and Y intercepts C:Symetry D:Asymptotes E:Interval of Increase/Decrease F:Local Max/Min G:Curvature and Inflection points
\[y=\sin^3x\]
Domain is all real numbers.
x intercept =
\[0=\sin^3x\]
\[\pi(n)\]
y intercept = 0
symetry = odd about the orgin
no asymptotes
\[f'(x)=3\sin^2xcosx\]
\[3\sin^2x=0\]
\[cosx=0\]
so my critical points for intervals of increase and decrease are
\[\pi/2,-\pi/2\]
Where are those 2 values coming from? From the cosine part?
the cosx=0 at pi/2
then the 3sin^2x=0, = 1-cosx/2=0 = cos2x=1
shoot now im not sure, somehow the book has the interval of 0<x<pi
\[cosx=0 \rightarrow x=\frac{ \pi }{ 2 }\pm \pi (n)\] Hmm your first set of critical points looks good. I think the next one you want to simply solve like this. \[3\sin^2x=0\] Dividing both sides by 3, then taking the square root of both sides, to get to this: \[sinx=0\rightarrow x=0 \pm \pi(n)\]
ok, so my intervals are inc(0,pi/2) dec(pi/2,pi)
my local max is f(pi/2) = 1
ok so for second derivative, is it safe to say that 3sin^2x is f and cosx is g? (using the product rule)
mhm that seems fine c:
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