You are Here: Home >< Maths

# Simplifying equation watch

Announcements
1. I am quite positive that the follwing equation would simplify to 0; however, I simply can't seem to make it work

y= (r-m)(r-n)(r-p) + (p-r)[(r-n)(r-p)+(r-m)(m-p)]

since I originally put r=(m+n)/2, it would also become

y=((m+n)/2-m)((m+n)/2-n)((m+n)/2-p) + (p-(m+n)/2)(((m+n)/2-n)((m+n)/2-p)+((m+n)/2-m)(m-p))

Help, guys? Do I just have to expand everything (innumerable opportunities for mistakes)..or is there a simpler way?
2. It won't be zero. eg, the first half will have a -mnp term but the second half won't (so it won't cancel).

However, if you leave r=(m+n)/2 in, it goes to zero. You can take out a factor of ((m+n)/2-p) to make your life a bit easier.
3. Thanks - I already used the normal expansion to finally prove that it goes to zero. Wish I had seen your reply earlier

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: March 15, 2008
Today on TSR

### Moving into halls?

How do unis decide who goes where?

### University open days

• University of Lincoln
Wed, 12 Dec '18
• Bournemouth University
Midwifery Open Day at Portsmouth Campus Undergraduate
Wed, 12 Dec '18
• Buckinghamshire New University
Wed, 12 Dec '18
Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams