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# C4 help needed watch

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2. May help in 2 seconds

3. I got stuck in last part
what I have done so far is substitute x and y in 9x-4y-15 and
expand it and got
4t^3 - 9t^2 -54t +135=0
I don't know how to factorize it further....
4. (Original post by Shaanv)
May help in 2 seconds

I posted now
5. (Original post by Qer)

I got stuck in last part
what I have done so far is substitute x and y in 9x-4y-15 and
expand it and got
4t^3 - 9t^2 -54t +135=0
I don't know how to factorize it further....
Work out the value of t at B. This will be a factor of the equation you have. Then u can do some division to get a quadratic in terms of t.
6. i tried factorising it and got t as -15/4 and 3.
try subing in=t into eqaution for x to try and find x.
7. (Original post by Shaanv)
Work out the value of t at B. This will be a factor of the equation you have. Then u can do some division to get a quadratic in terms of t.

can you tell me how you know that t-3 would be a factor(at b t=3) or how can I remember that thing?
8. (Original post by Qer)

can you tell me how you know that t-3 would be a factor(at b t=3) or how can I remember that thing?
Hmm, not sure i can explain it very well but ill have a go.

So the tangent has to pass through B as that is the condition given in the question. So u know when x=15 and y=0 the equation for the tangent is satisfied. But as u have the equation in terms of the parameter t, the t value corresponding to the point B will satisfy the equation, so that t value is a factor.

Sorry my explanations lacking, perhaps someone else could explain it more clearly.

Anyways hope i helped.

Which exam board are you with?
9. (Original post by Shaanv)
Hmm, not sure i can explain it very well but ill have a go.

So the tangent has to pass through B as that is the condition given in the question. So u know when x=15 and y=0 the equation for the tangent is satisfied. But as u have the equation in terms of the parameter t, the t value corresponding to the point B will satisfy the equation, so that t value is a factor.

Sorry my explanations lacking, perhaps someone else could explain it more clearly.

Anyways hope i helped.

Which exam board are you with?
edexcel
10. (Original post by Qer)
edexcel
With them too, i am also on that past paper grind.

The grind never ends😂
11. (Original post by Shaanv)
With them too, i am also on that past paper grind.

The grind never ends😂
are you doing M1?
12. (Original post by Qer)
are you doing M1?
I sat it last year. Managed to get 100 ums after doing sh** loads of past papers
13. (Original post by Shaanv)
I sat it last year. Managed to get 100 ums after doing sh** loads of past papers
GREAT

what u got in c1 &c2
14. (Original post by Shaanv)
I sat it last year. Managed to get 100 ums after doing sh** loads of past papers
100 ums!! thats amazing!! wow @Shaanv!! i did loads of paper as well but ended up with 82 ums which is pretty good but was expecting above 90.
15. (Original post by Qer)
GREAT

what u got in c1 &c2
C1 i got 95 and c2 i got 97. I am doing further maths as well and i feel like the more math i do the better i get at the stuff ive already done so that probably helped.

(Original post by Brudor2000)
100 ums!! thats amazing!! wow @Shaanv!! i did loads of paper as well but ended up with 82 ums which is pretty good but was expecting above 90.
Thanks, ur making me blush😂. 82 is still an awesome score and will help u get the grades u need.
16. (Original post by Shaanv)
Thanks, ur making me blush😂. 82 is still an awesome score and will help u get the grades u need.
Yh but 100 is just awesome!!! How r u finding A2 stuff. Do u do further maths??
17. I need little more help with some questions, have a look, please

18. (Original post by Qer)
...
You're not working with the entire range. Yes you got one part of the inequality, then look for the upper bound for which a straight horizontal line would intersect that graph twice.
19. (Original post by Qer)
I need little more help with some questions, have a look, please
What do you mean...?

So you solve and in the required range.

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