You are Here: Home

Quick indices question Tweet

Maths and statistics discussion, revision, exam and homework help.

Announcements Posted on
IMPORTANT: You must wait until midnight (morning exams)/4.30AM (afternoon exams) to discuss Edexcel exams and until 1pm/6pm the following day for STEP and IB exams. Please read before posting, including for rules for practical and oral exams. 28-04-2013
1. Quick indices question
I need to prove that . So we have

. But then I'm a bit confused on how they simplify it. Down to this:

2. Re: Quick indices question
try expanding the top.

Spoiler:
Show

you could also use the identity cos^2(theta) - sin^2(theta) = 1
Last edited by ReMos; 01-08-2012 at 09:59.
3. Re: Quick indices question

Does that help?
4. Re: Quick indices question
(Original post by music lover)
I need to prove that . So we have

. But then I'm a bit confused on how they simplify it. Down to this:

simplify the top by either expanding and collecting or using difference of two squares.
5. Re: Quick indices question
Got it. Thanks .