Curve sketching query (1 Viewer)

jusydoodle

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Hey guys,

When you are given a function to sketch, you would normally differentiate the f(x) to find the gradient/concavity to determine the nature of the stationary points right?

But when differentiating becomes too long, can you just draw the gradient function to determine the nature of the stat. points? I heard that this method isn't popular in 2U and 3U maths, but more in 4u..... does that mean that I shouldn't do it?


:confused::confused:
 

D94

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In 4U, I don't ever recall the need to draw the gradient function in order to sketch a graph. In fact, in 4U, they rarely ask for turning points, but rather critical points such as intercepts, asymptotes, nature of the curve as they reach these asymptotes, etc.

If it asks for the nature of the stationary points, then you should show the working out, rather than interpreting another graph. Unless it asks for the stationary points, you don't have to work them out and sketch them in accurately; you can just work out the critical points.
 

slyhunter

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what do you mean by "no" ?? :confused:
Hey guys,

When you are given a function to sketch, you would normally differentiate the f(x) to find the gradient/concavity to determine the nature of the stationary points right?

But when differentiating becomes too long, can you just draw the gradient function to determine the nature of the stat. points? I heard that this method isn't popular in 2U and 3U maths, but more in 4u..... does that mean that I shouldn't do it?


:confused::confused:
No to that.
 

cutemouse

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You actually can.

I think Trebla likes that method, if I recall correctly.
 

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