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Using substitution to find the exact value of the area issues[Integration]

The question: https://media.discordapp.net/attachments/480833140991066123/569195144926986280/Snapchat-335662147.jpg?width=289&height=513

For the area I got 2.5774 and I'm not sure if that's correct.

Also for the last question, I'm not sure as to how I can use substitution to integrate it like is that even possible?
seems reasonable answer to (a) & (b). What about (c)?

Show the working, pls, for the substitution processes you've done so far.
It works quite easily, by substitution.
Original post by OJ Emporium
The question: https://media.discordapp.net/attachments/480833140991066123/569195144926986280/Snapchat-335662147.jpg?width=289&height=513

For the area I got 2.5774 and I'm not sure if that's correct.

Also for the last question, I'm not sure as to how I can use substitution to integrate it like is that even possible?
Original post by begbie68
seems reasonable answer to (a) & (b). What about (c)?

Show the working, pls, for the substitution processes you've done so far.
It works quite easily, by substitution.

What I did:
https://cdn.discordapp.com/attachments/480833140991066123/569253589550104591/Snapchat-1901507530.jpg
(edited 5 years ago)
You've got du/dx wrong.

Which means you get the wrong function before you integrate.

try again?

or think about implicit diff of u^2 = x.

Original post by OJ Emporium
Original post by begbie68
You've got du/dx wrong.

Which means you get the wrong function before you integrate.

try again?

or think about implicit diff of u^2 = x.

Yeah no im completely confused here lol
differentiate 'root(x)'

what do you get?
Original post by OJ Emporium
Yeah no im completely confused here lol
why are you confused?

u = root x
you did du/dx and you got it wrong.

Try again.

Which bit is confusing?
Original post by OJ Emporium
Yeah no im completely confused here lol
i derived that and ended up getting du/dx = 1/2x and rearranged that to get 2du/x = dx

Original post by begbie68
why are you confused?

u = root x
you did du/dx and you got it wrong.

Try again.

Which bit is confusing?
Cool.

I'd usually leave it as 2udu = dx

Then, change limits
and sub for x, root x in the function

Simplify the function (if needed)

Integrate

So the limits thing and subtract, then simplify if needed.

Should be straight forward
Original post by OJ Emporium
i derived that and ended up getting du/dx = 1/2x and rearranged that to get 2du/x = dx
Original post by begbie68
Cool.

I'd usually leave it as 2udu = dx

Then, change limits
and sub for x, root x in the function

Simplify the function (if needed)

Integrate

So the limits thing and subtract, then simplify if needed.

Should be straight forward

Yeah i noticed i made a minor mistake from this, thank you man

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