Anyone able to give me a quick hand with a maths question?

GregoryNimmo

http://www.examinations.ie/index.php?l=en&mc=en&sc=ep&formAction=subject

The higher paper 2007, question 1 part c(i).

I dont understand how a(-p)squared) + b = 0
Can apsquared) = -b

Should ap(squared) not be minus ap(squared)?

Liveit

I looked at it and I was confused about it aswell.
How can something squared = -b ?
And I got it. You are assuming that b is a natural number, but actually it is a minus number and thats it.
So lets say if a=2 p=3 b=-18
a(-p)=-b
2(-3)^2=-(-18)
Which is right.
Hopefully I answered your question there.......god forbid I answered something that wasn't asked :pac:

Maybe_Memories

Haven't looked at the question.
But if (ap)^2 = -b, then b is a complex number.
You don't need to use that for the question I'd assume, just continue as normal..

Bruthal

GregoryNimmo wrote: »

http://www.examinations.ie/index.php?l=en&mc=en&sc=ep&formAction=subject

The higher paper 2007, question 1 part c(i).

I dont understand how a(-p)squared) + b = 0
Can apsquared) = -b

Should ap(squared) not be minus ap(squared)?

a(-p)squared can = -b because b is a negative value, so -b is a positive value.

**Timbuk2**

It makes sense if you think "Well b could be -3" or any other negative number. Thus -b is 3.

But just do that question as normal and the result will follow. You don't have to assume that b < 0 or anything.

mgsg27

In ap^2 = -b
The p^2 part is always going to be positive but the a and the b can be either positive or negative. a and b will also be opposite signs so that p^2 = -b/a will work out positive. for example -(-2)/3 is overall positive or -(2)/-3 is positive. I hope this makes sense

Overall anyway there's no need to worry about it. The sum works fine and fairly simply. Ignore anything that confuses you and work with what you do know. This is how I did it:
If x+p is a factor x = -p is a solution i.e when x=-p the equations will equal 0. Therefore the first equation is
ax^2 + b
a(-p)^2 +b = 0
ap^2 + b = 0
ap^2 = -b
p^2 = -b/a

If you want the rest of the sum I can do it for you.

GregoryNimmo

Thanks guys, all your replies were helpful. I basically have to teach myself honours maths because my teacher is braindead.