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# C3 Applications of Differentiation

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1. I am stuck on Q3,4,6,7,8,9,10,11 of the questions could anyone help? I have done Q1,2 &5.
2. What exactly is it that you are unable to do?
3. Finding the coordinates mainly (found my old account hence the different username)
4. (Original post by henb99)
Finding the coordinates mainly (found my old account hence the different username)
(Original post by henbnyc)
I am stuck on Q3,4,6,7,8,9,10,11 of the questions could anyone help? I have done Q1,2 &5.
Q3 - I can't see what gradient the book shows to I'll just refer to it as . Anyway, you have so you need to find by using an appropriate differentiation rule that you should know. Set and solve for to see at what x coordinates the gradient is .

Once you have your value(s) of , plug them back through to find your y coordinates.
5. (Original post by henb99)
Finding the coordinates mainly (found my old account hence the different username)
It may be easier to differentiate if you express it in the form .
6. $\int_{1}^{x}\sum r+6!\left ( 1 \right +x )x \mapsto x^2 \leq x\sqrt{1+x^{\pi}}$

How do I solve? ^
7. (Original post by Aklaol)
$\int_{1}^{x}\sum r+6!\left ( 1 \right +x )x \mapsto x^2 \leq x\sqrt{1+x^{\pi}}$

How do I solve? ^
8. (Original post by RDKGames)
Q3 - I can't see what gradient the book shows to I'll just refer to it as . Anyway, you have so you need to find by using an appropriate differentiation rule that you should know. Set and solve for to see at what x coordinates the gradient is .

Once you have your value(s) of , plug them back through to find your y coordinates.
I have tried this but only get one set of coordinates instead of two

When I differentiate using the quotient rule I get 1/(1+x)^2
9. (Original post by henb99)
I have tried this but only get one set of coordinates instead of two

When I differentiate using the quotient rule I get 1/(1+x)^2
That's correct. When it comes to square rooting, you should get 2 solutions because
10. (Original post by RDKGames)
That's correct. When it comes to square rooting, you should get 2 solutions because
So the gradient 1/9 is equal to 1+x^-2

-8/9=x^-2
11. (Original post by RDKGames)
Lmao you look like a killjoy and you sure are
12. (Original post by henb99)
So the gradient 1/9 is equal to 1+x^-2

-8/9=x^-2
Nope. So then
13. (Original post by BluntBluster)
Lmao you look like a killjoy and you sure are
Oh definitely a lot of joy posting complicated maths problems on a simple A-Level thread.
14. (Original post by RDKGames)
Nope. So then
Thank you so much I know how dumb I must sound, I have worked it out correctly

For question 4, when I differentiated I got 3x(x+1)^2 which is equal to the gradient 7

after this I got stuck again, there should only be one point (P)
15. (Original post by henb99)
Thank you so much I know how dumb I must sound, I have worked it out correctly

For question 4, when I differentiated I got 3x(x+1)^2 which is equal to the gradient 7

after this I got stuck again, there should only be one point (P)
Please state the original function, they are hard to see. Is it ??? If so, check your differential again.
16. (Original post by RDKGames)
Please state the original function, they are hard to see. Is it ??? If so, check your differential again.
I have got it to be (2,2)
17. (Original post by henb99)
I have got it to be (2,2)
Correct.
18. (Original post by RDKGames)
Correct.
What a levels to do btec level 3 ict with

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