x Turn on thread page Beta
 You are Here: Home >< Maths

# Maths Diff Question confusion Pls help watch

1. Hi All

Help needed with 2 Differentiation Questions.

Q= 2e^x + e^-2x
A= 2e^x + -2e^-2x

Why would they keep 2e^x in the answer ?
I do understand the -2e^-2x part though managed to work that one out correctly..

Q= sin(-8Q) the Q is supposed to be theta dont know how to write it on keyboard.
A= I would tend to give -8 Cos -8Q but the actual answer is

Kind regards
SZia
2. For the first part, when you differentiate 2e^x, you get 2e^x so it just looks odd.

As for the -8cos8Q part, note that cos(-Q) = cos(Q). They probably just wanted you to simplify it using that little trick.

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: September 24, 2010
Today on TSR

### Four things top students are doing

Over the Easter break

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