Additional Math Help HERE ONLY...!

[divineobsidian]

can anyone still help me with this real root stuff?

Nov 08 P2 Q3
Find the set of values for m for which the line y=mx+2 does not meet the curve y=x^2-5x+18

thanks, all help appreciated

[Padapop]

can anyone still help me with this real root stuff?

Nov 08 P2 Q3
Find the set of values for m for which the line y=mx+2 does not meet the curve y=x^2-5x+18

thanks, all help appreciated

b^2 - 4ac < 0

All u need to know i think

[archangel]

can anyone still help me with this real root stuff?

Nov 08 P2 Q3
Find the set of values for m for which the line y=mx+2 does not meet the curve y=x^2-5x+18

thanks, all help appreciated

yess =)

so the eqn will be joined together, since y is the common subject
becomes x²-5x+18=mx+2
then bring everything over
x²-5x-mx+18-2=0
x²-x(5+m)+16=0
so here the components of the quad eqn is fulfilled =)
so ax²+bx+c=0
a=1 b=(5+m) c=16

since tangent never touches the curve,
we use b²-4(a)(c) < 0
so substitute....
(5+m)²-4(1)(16)<0
25+10m+m²-64<0
m²+10m-29<0

solve quadratically, im sure u'll get ure answer  

[shan2391]

ahhhh thanks you guys!
so u mainly have to use permutations huh? okayyy

+ rep for all of u guys  

well that was what the answer at the back says =
maybe its the wrong answer printed... lol

as far as i know it when the Q. states select use combination otherwise permutation if arrangement is important

[shan2391]

guys this Q is always hard for me to solve can any 1 giv it a shot.
Nov08 Q4ii

[vanibharutham]

paper 1 or 2?

[shan2391]

paper 1 or 2?

oops P2

[vanibharutham]

{ = integration symbol, because i cant put the damn symbol on here

i)  Differentiate x ln x with respect to x
ii) Hence find {ln x dx.

First bit is easy
y = x lnx
Dy/dx = (1)(ln x) + (x)(1)
                                x
=> ln x + 1

The second part is asking you to use your first answer to help you find your integral of {ln x dx

ok

Well

we know that

{ln x + 1 dx = x lnx

therefore {ln x dx => x lnx - {1 dx

=> x lnx - x + c

To check if you answer is correct simply differentiate it

Y = x lnx - x + c
dY/dx = (1)(ln x) + (x)(1/x) - 1
         = ln x + 1 - 1
         => ln x

Hence we are correct

[sweetsh]

It seems im the only girl here taking this subject.
So guys I lost the prediction topics, what were the predictions?

[vanibharutham]

yea i got 1330 aswell... thnk the vector was 30 something i and 40 somethng j
SIMPLEST paper ive done so far... hope paper 2 stays that way...
PREDICTIONS FOR PAPER 2 anyone??
- permutations and combinations
- matrices
- sets
- functions
- more calculus (DUHH!!) perhaps approximate change, more area, probably another kinematics question(which will not be optional),
- simple vectors
- trigonometry equations
- graph sketching
- inequalities
- binomial expansions
don't forget to study what came in paper 1 cause they may bring it again!!! for instance, i think they might bring circular measure again cause the one in paper 1 was tooooo easy!!

[sweetsh]

Thank you!

[shan2391]

Thanks  vanibharutham

[vanibharutham]

did anyone do OR for the last question

[sweetsh]

What about relative velocity? Let's do an example from past papers

[shan2391]

What about relative velocity? Let's do an example from past papers

gud idea bringem on