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1 Attachment(s)
draw cos graph
hi,
i need to draw these on to a graph:
1. Y= cosx
2. Y= cosx+1
3. Y= cos(x+30)
i can do 1 and i think i have done number 2 correct but i can't do number 3.
here is what i have done for number 1 and 2, i have had a go at what i think number 3 would be:
Attachment 20809
i have labled them on the side also.
i think numbers 1 and 2 are correct but if they aren't please let me know and mainly is number 3 correct??
thanks!!!!!
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The thing with your drawing of the functions is that you've just drawn straight lines. They should be curves. You should use a program that's a bit better than paint at drawing functions. I myself use graph 4.3. Look the functions up there.
Anyways, it should be like this:
graph one should look like a periodic curve that repeats itself every 360 degrees, i.e. it goes from 1 to -1 on the y-axis after 180 degrees, and then goes back to 1 etc, starting at the point (0,1).
Graph two should look like graph one, except for the fact that it's displaced by 1 in a positive direction on the y-axis.
Graph three should look like graph one also, but should be displaced by 30 degrees to the left.
Best wishes, and good luck with trigonometry!
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in my book i have them as curves but i wasn't able to do that on paint because i didn't want to do it free hand! so what i have draw for B or graph 2 is correct??
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No, because you have negative values on it.
is the graph of
moved up one unit on the y axis which means that while the range it  + 1 < 2)
For the sake of completion I've added the graphs (in a spoiler). cos(x) is in green, cos(x)+1 is in blue and cos(x+30) is in orange
nb: this graph is in radians (pi/6 = 30 degrees). pi/2 = 90 degrees, pi = 180 degrees, 3pi/2 = 270 degrees and 2pi = 360 degrees
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1 Attachment(s)
would this be it then?? (it is labeled 2)
Attachment 20811
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Looks fine to me (aside from the technical issues of lines instead of curves of course)