Help me understand this expansion
- Thread starter thickmax
- Start date
pka
Elite Member
- Joined
- Jan 29, 2005
- Messages
- 11,976
The standard expansion is \((a+b )^2=a^2+2ab+b^2\)
in \(\left(1-\dfrac{x^2}{2}\right)^2\) we have \(a=1~\&~b=\dfrac{-x^2}{2}\)
So that \(1^2~,~2(1)\left(\dfrac{-x^2}{2}\right)~\&~\left(\dfrac{-x^2}{2}\right)^2=1-\left({x^2}\right)+\left(\dfrac{x^4}{4}\right)\)
Can you finish?
in \(\left(1-\dfrac{x^2}{2}\right)^2\) we have \(a=1~\&~b=\dfrac{-x^2}{2}\)
So that \(1^2~,~2(1)\left(\dfrac{-x^2}{2}\right)~\&~\left(\dfrac{-x^2}{2}\right)^2=1-\left({x^2}\right)+\left(\dfrac{x^4}{4}\right)\)
Can you finish?
Last edited:
D
Deleted member 4993
Guest
D
Deleted member 4993
Guest
REALLY!
Check response #2 and work through line-by-line, using pencil & paper.
What does the first line ( of the response #2) say ?. Write it out! Do you agree with that statement?
Last edited by a moderator:
D
Deleted member 4993
Guest
In response# 3 you did NOT state that you do not follow:
I stress again - please work with pencil-paper, don't just stare at the glowing screen.
Is this your first-course in algebra? Like pka stated that equation is "standard" and used quite often (along with many other equations).
Yeah, but again, when a step is missed, what I'm looking for has changed....I'm not that clever to see things without every step!
I will take your point on board with the pencil-paper
Not really, I'm 25 and had completed a HNC 4 years ago...I'm hoping to go to Univesity in September to study Mechatronics and have to do an A level top up course to fulfil the entry requirements, but it is proving very difficult and I'm not sure this level, or high level of maths is for me...
Considering changing the degree of choice to design and construction management...