Answer my stupid maths question! (1 Viewer)

[Dylanamali]

When dividing a line externally in a ratio, to which number do you apply the negative to?

E.g. A is the point (-2,-1) and B is the point (1,5). Find the coordinates of the point Q which divides AB externally in the ratio 5:2.

I always thought you just stick it in front of the 5, however the answers put it in front of the 2 and each of these produced different results.

So please tell me which one and the reasoning..

Thank you for answering my STUPID question haha =)

 

[SpiralFlex]

Does not matter, they are still in the same ratio.

Think of



and



Same thing.

 

[Drongoski]

Either one but not both.

 

[SpiralFlex]

Also. The only stupid question you can ask is the one that you don't ask. So you better ask or else you will not know.

 

[Dylanamali]

Thank you both, haha..

 

[Dylanamali]

ANOTHER MATHS Q:


Evaluate exactly, sorry about the brackets, meant to be around the sin 7pie on 6

 

[Hermes1]

-pi/6

do u want an explanation?

 

[Dylanamali]

its worth 2 marks.. I know what I'm doing but I'm not sure if I'm getting 2 marks

I just get the exact value for sin 7pi/6 which is -1/2 then sin-1 that.. to get -pi/6.

 

[Hermes1]

its worth 2 marks.. I know what I'm doing but I'm not sure if I'm getting 2 marks

I just get the exact value for sin 7pi/6 which is -1/2 then sin-1 that.. to get -pi/6.

you have to do this:

(bcuz inverse sin x is an odd function)

 

[Hermes1]

its worth 2 marks.. I know what I'm doing but I'm not sure if I'm getting 2 marks

I just get the exact value for sin 7pi/6 which is -1/2 then sin-1 that.. to get -pi/6.

this is also right obviously. bcuz if its only 2 marks they wont really care wat way u do it as long as u show a few lines of working

 

[JennaJameson]

no his way is completely legit

your way is long and tedious

 

[Dylanamali]

tyvm

 

[Hermes1]

no his way is completely legit

your way is long and tedious

his way is legit. but wat if u get something like 9pi/10. then my way is best utilised.

 

[zxreth]

ANOTHER MATHS Q:


Evaluate exactly, sorry about the brackets, meant to be around the sin 7pie on 6

CSSA 2010 lol was doing it myself earlier

 

[Dylanamali]

did you FIND IT a lil difficult..??? like I just did CSSA 2009 and it was preety sweet, moved onto 2010 and was like ****.. this aint that nice..

 

[Hermes1]

did you FIND IT a lil difficult..??? like I just did CSSA 2009 and it was preety sweet, moved onto 2010 and was like ****.. this aint that nice..

CSSA 2009 was really easy. 2010 was also pretty easy, i only had a problem with the last part of the parametrics question, that was only 1 mark tho.
The 2010 paper the las question was weird as.

 

[umz93]

Hey where did u find 2010 cssa for ext1 maths?

 

[Shadowdude]

Pro-tip: Draw a diagram and figure it out that way.

 

[Omnipotence]

Don't you substitute the values into the formula?
Q(x) = mx(2)-nx(1)/m-n
and
Q(y) = my(2)-nx(1)/m-n

 

[Omnipotence]

^ Thats how I usually do it, never faulted.