Preliminary mathematics marathon (1 Viewer)

[hscishard]

2000/root 21

 

[ohexploitable]

2000/root 21

Try again

 

[hscishard]

root4000 over root 21

 

[ohexploitable]

root4000 over root 21

Try again

 

[hscishard]

Omg'd.

A man in a rowing boat is 6km from the nearest point A on the shore. He wants to reach as soon as possible to point B that is a further 20km down the shore from A. If he can row at 8km/h and run 10km/h (pretty slow man), how far from A should he land?

 

[ohexploitable]

Omg'd.

A man in a rowing boat is 6km from the nearest point A on the shore. He wants to reach as soon as possible to point B that is a further 20km down the shore from A. If he can row at 8km/h and run 10km/h (pretty slow man), how far from A should he land?

8 km.

 

[hscishard]

8 km.

What's the difference between the method in the two questions then?!

 

[ohexploitable]

What's the difference between the method in the two questions then?!

No difference in methods, exactly the same just with different values.

 

[hscishard]

Annoying..what's the answer?

 

[ohexploitable]

 

[hscishard]

Finally got it. OMG.
Initially I just converted 1000 and 5000 to 1km and 5km. Thus the pythag, root x^2 + 1
After the first attempt I realised the speed was in m/s.

Went root (x^2+1000)

 

[random-1005]

That helps heaps. My point B was like a 5km radius.

In 9b) i-iv are easy..
Not sure on v though. I'm sure this part is similar to the question above.

9 b part v is easy as well (but long), it just involves going back to part A and changing your cost formula to include the new the price given, and then you have to go through the whole process again differentiate , equal to zero etc. CHECK YOUR MAXIUM/MINIUM (even if you only have one answer) .

 

[ohexploitable]

New Question:

An A4 sheet of paper has equal squares cut from each corner to form a rectangular prism. What sized squares will give it the greatest volume?

 

[hscishard]

New Question:

An A4 sheet of paper has equal squares cut from each corner to form a rectangular prism. What sized squares will give it the greatest volume?

Lol. What are the measurements of an A4 page?

I've done this b4.

 

[ohexploitable]

A4 is 210x297 mm.

 

[hscishard]

A4 is 210x297 mm.

I cbf doing it then.
Let someone else do it

 

[random-1005]

New Question:

An A4 sheet of paper has equal squares cut from each corner to form a rectangular prism. What sized squares will give it the greatest volume?

MAX/MIN questions are easy/boring, move along lol

 

[random-1005]

if a and b are the roots of x^2 +px +q=0

find the equation whose roots are (a-b) and (b-a)

 

[hscishard]

if a and b are the roots of x^2 +px +q=0

find the equation whose roots are (a-b) and (b-a)

At first glance, p=0 and q<= 0

 

[random-1005]

At first glance, p=0 and q<= 0

an equation, not a condition