curve sketching Q (1 Viewer)

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i)
sketch, without the use of calculus, on the same set of coordinate axes and over the domain -2pi <= x <= 2pi, the three functions:

f(x) = sinx , g(x) = sin<sup>2</sup>x and h(x) = f(x) + g(x) done

ii) on separate coordinate axes sketch y = Ln(h) cannot do

so how would you go about sketching this step-by-step? :confused:
 
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gman03

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whenever h(x) --> 0, then y -> -infinity
for h <= 0, y(x) is not defined
when h = 1, y = 0
when h = e, y = 1...
when when h is increasing, y is increasing.... and so on

Hope this help
 

gman03

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oops i thought it was ln.... in that case i dunno about In
 

:: ck ::

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umm if u know how to draw the first one

basically to draw the Ln graphs

when h(x) crosses y = 1

theres an x intecept

when h(x) hits the x axis
theres a vert asymptote

when h(x) is between 0 and 1
Ln graph is under x axis

thats all u really need to know :)
 
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Originally posted by :: ryan.cck ::
umm if u know how to draw the first one

basically to draw the Ln graphs

when h(x) crosses y = 1

theres an x intecept

when h(x) hits the x axis
theres a vert asymptote

when h(x) is between 0 and 1
Ln graph is under x axis

thats all u really need to know :)
hmm.. i don't really get it
h(x) never crosses y=1, it crosses at the origin

here's the answer..but i still don't know how to do it :(
 

:: ck ::

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well look at ur graph

its always under the x axis coz as u said.. it never crosses y = 1

and as it crosses the origin u have all of these asymptotes .. which is present in the attachment u posted
 

CM_Tutor

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Originally posted by ToO LaZy ^*
i got another q
sketch the curve
y = tan<sup>-1</sup>(x) + tan<sup>-1</sup>(1/x)
any takers? :p
Show that dy/dx = 0.
The domain is {x: x &ne; 0}
Evaluate tan<sup>-1</sup>x + tan<sup>-1</sup>(1 / x) at x = 1 and x = -1
You should be able to sketch it from there.
 

schmeichung

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do u have the answer for this?
y = tan-1(x) + tan-1(1/x)

jus wanna check if im correct :)
 
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yeah..
it's a straight horizontal line from 0 -> infinity at y = pi/2
and another straight horizontal line from 0 -> -infinity at y = -pi/2
 

CM_Tutor

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ToO LaZy ^* said:
yeah..
it's a straight horizontal line from 0 -> infinity at y = pi/2
and another straight horizontal line from 0 -> -infinity at y = -pi/2
With open circles at (0, &pi; / 2) and at (0, -&pi; / 2).
 

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