Curve Sketching (1 Viewer)

[housemouse]

Curve sketching is soooooooooo confusing when my teacher at school teaches it and I have no idea how to draw a graph after the holidays

So how would you sketch y = xsinx and y = cosx/x??????????

 

[Riviet]

So how would you sketch y = xsinx and y = cosx/x??????????

Hehe, I was doing some just now. After you do alot, you seriously get efficient at sketching curves.
For y=xsinx, you can let f(x)=x and g(x)=sinx, draw both of the guide graphs on the same number plane, and multiply the y-coordinates for each value of x and plot it. For division, you can let f(x)=cosx and g(x)=x and divide the y-coordinates of each graph and plot points.

 

[adgala]

or to draw cosx/x (a bit easier), draw cosx and 1/x and multiply both graphs for cosx/x (multiplying is easier than dividing )

 

[housemouse]

how exactly do you mutiply two lines?
i knew i had to do that yesterday however do not know how

 

[Trev]

Take the y value of one and multiply that by the y value of the other line...

 

[pLuvia]

There is the long way for finding the asymptotes, the gradient, signs etc. But that one is the most efficient