You are Here: Home >< Maths

# Transformations of graph of y = sin x watch

Announcements
1. Graphs HERE

What are the equations of these graphs? (in the form y = a sin (bx) + c) (transformations of the graph y = sin x)
2. In the second one, you can see that there are 6 repetions of the graph, where there would normally only be a quarter of a period between 0 and 90 - so it's oscillating 24 times faster. So you have something with

sin(24x)

in it. Also you can see that the graph goes from 45 at its minimum, to 145 at its maximum (spanning 100 units) whereas a normal sin graph goes from -1 to 1 (spanning two units). So you have

50sin(24x)

Then notice that the graph is a mirror image to what you'd expect, as 'sin' normally goes upwards from the origin. So you're looking for a

-50sin(24x)

And finally, sin(0) is normally zero, but here it's 90, so your final equation for the graph is

y = -50sin(24x) + 90
3. the first one seems to be

-3sin(x/3) -1

the period is 3*normal hence the division by 3 . the amplitude is 3*normal hence the multiplication by 3. it is upside down hence the negative at the start. it has been moved down 1 unit hence the -1 at the end.

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: November 16, 2005
Today on TSR

### Official 2019 Cambridge Interview Thread

Discuss upcoming interviews...

### University open days

• Heriot-Watt University
School of Textiles and Design Undergraduate
Fri, 16 Nov '18
• University of Roehampton
Sat, 17 Nov '18
• Edge Hill University
Faculty of Health and Social Care Undergraduate
Sat, 17 Nov '18
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