This discussion is now closed.

Check out other Related discussions

- SQA Exam Discussions 2024
- A-level Exam Discussions 2024
- GCSE Exam Discussions 2023
- exam season in uni?
- GCSE Exam Discussions 2024
- Can you take an A level exam after May/June?
- Ace your exams without stress
- How to sit in GCSE Exams in November 2024
- I'm in Year 11 and confused about the gaps between GCSE exams
- Ace your exams without stress
- Going through my University’s complaints process
- AS level accounting for private candidate
- More GCSES to get into college
- GCSE Biology Study Group 2022-2023
- When are December exams released from the registry? UofG
- Deferring University exams
- Late for Exam - University of Manchester
- Post Exam Blues
- A level re-sit
- How to Self Study Computer Science?

Help!! The exam is in a few days and I’m confused…

This is for the maths as-level exam:

1) The line with equation y = 3x + 1 cut the curve with equation y = x^2 + 4x – 5 at the points A and B. Find the length of AB.

(I found the coordinates A(-3, -8) and B(2, 6) but I don’t know what to do next…

2) On a journey, the average speed of a car is v m s^-1. For v to be bigger or equal to 5, the cost per kilometre, C pence, of the journey is modelled by: C = 160/v + v^2/100

Using this model,

a) Show, by calculus, that there is a value of v for which C has a stationary value, and find this value of v.

b) Justify that this value of v gives a minimum value of C.

c) Find the minimum value of C and hence find the minimum cost of a 250 km car journey.

(I didn’t even know we DID calculus, whatever it is, is this in the syllabus cuz it’s not in my Edexcel book)

3) Straight line L1 crosses the y-axis with the equation y = 3/2x – 2. The point Q has the coordinates (5, -3). Straight line L2 is perpendicular to L1 and passes through Q.

a) Find the equation for L2 in the form ax + by = c, where a, b and c are integer constants.

Would appreciate any help given .

BB

This is for the maths as-level exam:

1) The line with equation y = 3x + 1 cut the curve with equation y = x^2 + 4x – 5 at the points A and B. Find the length of AB.

(I found the coordinates A(-3, -8) and B(2, 6) but I don’t know what to do next…

2) On a journey, the average speed of a car is v m s^-1. For v to be bigger or equal to 5, the cost per kilometre, C pence, of the journey is modelled by: C = 160/v + v^2/100

Using this model,

a) Show, by calculus, that there is a value of v for which C has a stationary value, and find this value of v.

b) Justify that this value of v gives a minimum value of C.

c) Find the minimum value of C and hence find the minimum cost of a 250 km car journey.

(I didn’t even know we DID calculus, whatever it is, is this in the syllabus cuz it’s not in my Edexcel book)

3) Straight line L1 crosses the y-axis with the equation y = 3/2x – 2. The point Q has the coordinates (5, -3). Straight line L2 is perpendicular to L1 and passes through Q.

a) Find the equation for L2 in the form ax + by = c, where a, b and c are integer constants.

Would appreciate any help given .

BB

Blush Babe

Help!! The exam is in a few days and I’m confused…

This is for the maths as-level exam:

1) The line with equation y = 3x + 1 cut the curve with equation y = x^2 + 4x – 5 at the points A and B. Find the length of AB.

(I found the coordinates A(-3, -8) and B(2, 6) but I don’t know what to do next…)

2) On a journey, the average speed of a car is v m s^-1. For v to be bigger or equal to 5, the cost per kilometre, C pence, of the journey is modelled by: C = 160/v + v^2/100

Using this model,

a) Show, by calculus, that there is a value of v for which C has a stationary value, and find this value of v.

b) Justify that this value of v gives a minimum value of C.

c) Find the minimum value of C and hence find the minimum cost of a 250 km car journey.

(I didn’t even know we DID calculus, whatever it is, is this in the syllabus cuz it’s not in my Edexcel book)

3) Straight line L1 crosses the y-axis with the equation y = 3/2x – 2. The point Q has the coordinates (5, -3). Straight line L2 is perpendicular to L1 and passes through Q.

a) Find the equation for L2 in the form ax + by = c, where a, b and c are integer constants.

Would appreciate any help given .

BB

This is for the maths as-level exam:

1) The line with equation y = 3x + 1 cut the curve with equation y = x^2 + 4x – 5 at the points A and B. Find the length of AB.

(I found the coordinates A(-3, -8) and B(2, 6) but I don’t know what to do next…)

2) On a journey, the average speed of a car is v m s^-1. For v to be bigger or equal to 5, the cost per kilometre, C pence, of the journey is modelled by: C = 160/v + v^2/100

Using this model,

a) Show, by calculus, that there is a value of v for which C has a stationary value, and find this value of v.

b) Justify that this value of v gives a minimum value of C.

c) Find the minimum value of C and hence find the minimum cost of a 250 km car journey.

(I didn’t even know we DID calculus, whatever it is, is this in the syllabus cuz it’s not in my Edexcel book)

3) Straight line L1 crosses the y-axis with the equation y = 3/2x – 2. The point Q has the coordinates (5, -3). Straight line L2 is perpendicular to L1 and passes through Q.

a) Find the equation for L2 in the form ax + by = c, where a, b and c are integer constants.

Would appreciate any help given .

BB

For question one...you have the co-ordinates....use these to find horizontal and vert distance then use pythagoras' theorum.

Wait for question 2....i haven't read it yet...

G

Erm...not too sure on question 2....cos i don't fully understand the question!

But....i think that it wants you to treat C=...etc. as the formula for a curve...so differentiate it and set to 0 (i.e. stationary points), then finish the question.

Question3...find perpendicular gradient for L1...sub it ito the formula for a straight line using Q as reference points...and rearrange to find L2's equation...hope it helps.

G

But....i think that it wants you to treat C=...etc. as the formula for a curve...so differentiate it and set to 0 (i.e. stationary points), then finish the question.

Question3...find perpendicular gradient for L1...sub it ito the formula for a straight line using Q as reference points...and rearrange to find L2's equation...hope it helps.

G

gzftan

For question one...you have the co-ordinates....use these to find horizontal and vert distance then use pythagoras' theorum.

Wait for question 2....i haven't read it yet...

G

Wait for question 2....i haven't read it yet...

G

Thanks for Qs 1....Im so thick

Blush Babe

Thanks for Qs 1....Im so thick

No probs....sometimes i miss the simplest things...and then someone points it out to me...and i feel like a right plonker!

Seriously tho...sometimes your mind gets stuck in one way of doing something...so when the time comes to use a different method...you can't see it! Just take your time when answering questions...and try and look at it from as many different angles (haha..maths pun!!) as possible.

I find that helps loads, hope it helps you.

G

Nylex

Calculus is differentiation and integration. Surely "stationary value" makes you think of differentiating?

Oh....so you use diff to find the gradient/acceleration...Sorry if I'm stating the obvious but our teacher sucks and he never told us what they're used for. Thanks though.

BB

gzftan

No probs....sometimes i miss the simplest things...and then someone points it out to me...and i feel like a right plonker!

Seriously tho...sometimes your mind gets stuck in one way of doing something...so when the time comes to use a different method...you can't see it! Just take your time when answering questions...and try and look at it from as many different angles (haha..maths pun!!) as possible.

I find that helps loads, hope it helps you.

G

Seriously tho...sometimes your mind gets stuck in one way of doing something...so when the time comes to use a different method...you can't see it! Just take your time when answering questions...and try and look at it from as many different angles (haha..maths pun!!) as possible.

I find that helps loads, hope it helps you.

G

LOL. Cheers.

Linx

Help!! i have a psychology exam in a few days and i have sooo many names and dates to remember i don't know where to start, any tips would probably save my life!! thanks.

Names and dates? Sounds like history....just keep writing them down, even rhyme them if it helps . You can also record them on a tape and play it to yourself whilst you are sleeping. Also post-it them on your bathroom mirror so you see them, and hopefully memorise them, while you're brushing teeth and doing other essential groomings .

Hope this helps...

BB

P.S. I never tried any of them cuz I'm too lazy but the things I come up with....I should write a book.

- SQA Exam Discussions 2024
- A-level Exam Discussions 2024
- GCSE Exam Discussions 2023
- exam season in uni?
- GCSE Exam Discussions 2024
- Can you take an A level exam after May/June?
- Ace your exams without stress
- How to sit in GCSE Exams in November 2024
- I'm in Year 11 and confused about the gaps between GCSE exams
- Ace your exams without stress
- Going through my University’s complaints process
- AS level accounting for private candidate
- More GCSES to get into college
- GCSE Biology Study Group 2022-2023
- When are December exams released from the registry? UofG
- Deferring University exams
- Late for Exam - University of Manchester
- Post Exam Blues
- A level re-sit
- How to Self Study Computer Science?

Latest

Trending

Last reply 1 day ago

Achieved top grades (3 A*) at school, but not sure uni is right for me