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

# OCR C4 Intergration (Hard)... rep+ watch

1. Hey guys,

I am stuck and would appreciate some help!

1) f(x)= sin1/2x + cos1/3x

write down another value of X (not 0) for which f(x)=f(0) and f'(x)=f'(0)

So I got sin1/2x + cos1/3x =1
then I have no idea what to do LOL!

I also got 1/2cos1/2x- 1/3sin1/3x =1/2

Again I have no idea how to simplifiy or anything...

Help would be appreciated and plus rep given.
2. Consider sin1/2x + cos1/3x =1.

If x=even multiple of pi, then the sine term vanishes.
So which values of x=2pi, 4pi, 6pi,...etc give cos(x/3)=1 ?
Clearly x=6pi, 12pi, 18pi,...etc will work.

Similarly for 1/2cos1/2x- 1/3sin1/3x =1/2, the sine term vanishes for x=multiples of 3pi = 3pi, 6pi, 9pi, 12pi,...etc
So which of these values give cos(x/2)=1 ?

Which solution is common to both equations?

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: April 7, 2011
Today on TSR

### University rankings 2019

Cambridge at number one

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