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Nazyma
PLEASE HELP ME!!!!!!! REALLY IMPORTANT!!!!!!!!! y = −5 cos x On what intervals within [0, T) is f increasing? (T is the period of the function. Enter your answer using interval notation. If an answer does not exist, enter DNE.)
hm. have you learned derivatives yet?
That's the graph http://www.wolframalpha.com/input/?i=y%3D-5cos%28x%29
ok, so all you have to do is draw out the function and I guess just look at it.
yes, but can you plz exactly say where it is increasing?
notice that it starts at -5, right? it keeps going up from there. it's still moving up once it crosses the x axis.
once it hits pi, it starts to move down instead.
therefore your answer is [0, pi]. hopefully that helped.