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Minimum Point On A Curve

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This thread contains the many tribulations of a TSR user
you differentiate it, then put your answer equal to zero. Also this is on the normal IGCSE syllabus, cos i have my exam tomorrow and it is one of the topics i am revision :frown:
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Original post by M_E_X
The minimum point will be when x = -4. You have to set the inside of the bracket to zero.

Sub x= -4 in to the original equation to find the value of the function at this point.

source: http://www.mathcentre.ac.uk/resources/workbooks/mathcentre/web-completingsquare1.pdf (section 4)


The minimum point is at x = 4 not x = -4 though.
(edited 8 years ago)
Original post by jonny23563
Differentiate, set this equal to 0 to find stationary points.

Check values either side of any stationary points to see whether they are minimum or maximum


There's no need to check. A quadratic graph has the shape of a parabola, and if the coefficient of x^2 is positive, it will only have one minimum point and no other stationary points.
Reply 25
Original post by Dingooose
There's no need to check. A quadratic graph has the shape of a parabola, and if the coefficient of x^2 is positive, it will only have one minimum point and no other stationary points.

I think you'll find plenty of new threads to reply to.

There's no need to resurrect a 6 year old thread :smile:
Original post by notnek
I think you'll find plenty of new threads to reply to.

There's no need to resurrect a 6 year old thread :smile:


Whoops, my bad.
Double necro! It got revived once more in 2012, he's just keeping the 3-year cycle going
its as level
The answer is (4,7) because the bracket needs to be zero so its the opposite sign therefore 4. And the y is the exact number at the end so 7.
Reply 30
Original post by jklmn
You don't need to know that at gcse???


It's part of the syllabus now😂

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