2nd diff and turning point of curve

[long vine]

can someone do this can’t get correct ans

[feral escarp]

For what part

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all of it

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mainly part 1 though

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What did u get for second derivative

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Whats the answer meant to be

Sry for late reply

Ill send workings

@long vine

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i don’t have it 😅

teacher gave it without one

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How yk ur wrong then

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friends all got different ans from me

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What did they get

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can’t remember saw it at 9 was like 6cos^2x something

what did you get?

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6cosec^4x-4cosec^2x

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can you show how

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Ur answer is correct just get it all in terms of cosec

identity

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idk how to

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didnt finish second part btw but yh just solve and plug into second deriv

[long vine]

oh so u just subbed in one of the trig rules

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for a ?

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yea

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just used the identity

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yea

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yea

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i was nearly there then😅

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Yea

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need to learn the identities abit more

how do u finish part ii)

is it pi/2 and 3/2pi

[feral escarp]

yh then plug them in original y=csc^2 x

To find the y