You are Here: Home >< Maths

# C3 Domain and Range help.

Announcements Posted on
Four hours left to win £100 of Amazon vouchers!! Don't miss out! Take our short survey to enter 24-10-2016

1. Thats the question, I get part A, however I do not understand how to do part B and C could someone help me please

2. (Original post by Jahmed228)

Thats the question, I get part A, however I do not understand how to do part B and C could someone help me please

First off you are restricted to x >/= 0 by the fact that this is the domain for g. Then f is only defined on 0 </= x </= pi, so fg is only defined when 0 </= g(x) = x +pi/2 </= pi This yields -pi/2 </= x </= pi/2 but since x >/= 0 we restrict this hence the answer

Note then that cos(x + pi/2) = -sinx, and on the domain you just found the range is easily deduced

## Register

Thanks for posting! You just need to create an account in order to submit the post
1. this can't be left blank
2. this can't be left blank
3. this can't be left blank

6 characters or longer with both numbers and letters is safer

4. this can't be left empty
1. Oops, you need to agree to our Ts&Cs to register

Updated: June 21, 2016
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:
Today on TSR

### Who is getting a uni offer this half term?

Find out which unis are hot off the mark here

Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read here first

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams