Chapter 5 Radians - Year 2

Question 1

What is a radian?

Answer 1

1 radian is the movement of 1 radius length around the circumference of a circle

Question 2

Answer 2

Question 3

Answer 3

Question 4

What is the arc length of a circle in radians?

Answer 4

Question 5

What is the area of a sector of a circle in radians?

Answer 5

Question 6

What is the formula for this area:

Answer 6

Question 7

How would you solve something like sin3x=(sqr(3))/3)
Solve between 0<x<2pi

Answer 7

Let y=3x
Then solve it normally, looking at the cast diagram to get the solutions

You need to remember to adjust your area of answers

(Is there a quicker way)?

Question 8

What is the small angle approximations for sinx?

Answer 8

Sinx=x

Question 9

What is the small angle approximation for cosx?

Answer 9

Question 10

How are you support to substitute in your small angle approximations?

Answer 10

Sin2x and tanyx you just write 2x and yx (where y could be any number) respectively

For cos4x you write 1- (4x)^2/2

Question 11

What is the obscure thing about small angle approximations?

Answer 11

If your final answer has x in it then (As you are assuming x is tending towards 0) you can get rid of the x terms