Mathematics solutions (1 Viewer)

[Gillywilly]

A1 = 29227(1.005) + M(1.005)

A2 = 29227(1.005)^2 + M(1.005)^2 + M(1.005)
= 29227(1.005)^2 + M(1.005 + 1.005^2)

A3 = you get the point


An = 29227(1.005)^n + M(1.005+1.005^2+...+1.005^n)
= 29227(1.005)^n + M(a(r^n-1)/(r-1))

After 240 months An = 800000. So solve the equation when n = 240 and An = 800000. Ends up with the answer in the OP.

that's 8c(ii) LOL

 

[Ferox]

The radius of the cylinder is the x value at C.

since y = x^2, then at y=h, x = sqrt(h).

The volume of the cylinder is the pi*radius^2*height = pi*sqrt(h)^2*h. Put that under the volume of the paraboloid in pt i and you get half.

 

[jamesfirst]

lol that's what i thought at first, but remember the area underneath the x axis has a negative value, so, -4 + 2 = - 2.

But you absolute value the negative area

 

[rrlm910]

What was question 3a about again?

 

[OmmU]

But you absolute value the negative area

If you are referring to the 'evaluate the integral' final part I put -2.. For the area it would have been something like 8.

 

[OmmU]

What was question 3a about again?

The skyscraper question.

 

[someth1ng]

I got 17 for 5.a.ii - LOL

 

[jamesfirst]

Guys are these solutions correct?

 

[jamesfirst]

My proof for 9aii)

If AB = AC, and AD = AE (given)
Then BC is parallel to DE (equal intercept theory)

RTP triangle BCF is congruent to triangle DFE
Angle BFC = DFE (vertically opposite)
Angle FBC = FED (alternate angles in parallel lines)
Therefore triangle BCF is congruent to triangle DFE (AAA)

We know BC : DE = 1 : 2,

Hence in similar triangles BCF and DFC

BC : DE = BF : FE (corresponding sides)
Therefore BF : FE = 1 : 2

Is this reasoning correct?

wtf? There is not congruency rule with AAA.

There is a similar triangle rule with AA.. therefore by putting in congruent triangle, you are incorrect. You can't have a 'ratio' with congruent triangles anyway.



And, instead of "(equal intercept theory)" I wrote "equal transversals of parallel lines"

 

[jamesfirst]

I did this. I think its correct!

are you a troll ???


you do 4 unit.

 

[jamesfirst]

If you are referring to the 'evaluate the integral' final part I put -2.. For the area it would have been something like 8.

no ??


Area was like 6 because it didn't take into consideration of area 'A'.


anyway, I knew it was either going with the integral or using the area.

BUT the question did say "from the previous answers", so I just assumed that it was area.


Edit: how did you guys prove 9 b ii) ?

 

[damo_g]

The answers in the first post for question six are correct. The area from 0 to 2pi is 8 and the value from pi/2 to 2pi is -2. Value can be negative, area no.

 

[Tasha270494]

I got different for 5a)iii
No. of members on day 12 = 55296 (like you said in (i))
And then don't you multiply that by 0.5 =27648 cents
Convert to nearest dollar = $276 ?

 

[jukeboxk]

For 1 (f) the answer to the simplest form would be 2(√5 + √3)

 

[OmmU]

For 1 (f) the answer to the simplest form would be 2(√5 + √3)

Claps for Q1 right!

 

[barbernator]

I got different for 5a)iii
No. of members on day 12 = 55296 (like you said in (i))
And then don't you multiply that by 0.5 =27648 cents
Convert to nearest dollar = $276 ?

It said "per person per day", so you had to find the sum of the members up to day 12.

 

[Gillywilly]

for question 4(e)
could you also have written
abs(x) - 2 <= 0
4 - x^2 >= 0
yes? no?

 

[Entity]

It said "per person per day", so you had to find the sum of the members up to day 12.

Yeah it comes to around 1452 or something like that?

 

[cheschirecat]

I got different for 5a)iii
No. of members on day 12 = 55296 (like you said in (i))
And then don't you multiply that by 0.5 =27648 cents
Convert to nearest dollar = $276 ?

Yes there are that amount of members but they're not asking how much money the site earned on day 12 it is asking how much money it earned during the first 12 days so the answer would be:
27*0.005((2^12)-1)/(2-1)

 

[cheschirecat]

For 1 (f) the answer to the simplest form would be 2(√5 + √3)

I'm guessing that they would accept both, I chose to interpret "simplest form" as being fully simplified not just having a simple layout.

wtf? There is not congruency rule with AAA.

There is a similar triangle rule with AA.. therefore by putting in congruent triangle, you are incorrect. You can't have a 'ratio' with congruent triangles anyway.



And, instead of "(equal intercept theory)" I wrote "equal transversals of parallel lines"

I think he meant similar triangles but accidentally wrote congruent in his post, reasonable enough mistake to make.