Important Formula

Question 1

What is the formula for the area of a trapezium?

Answer 1

1/2 (a+b) x h

Question 2

What is the cross section of a prism?

Answer 2

A cross section is the shape we get when cutting straight through an object

Question 3

What is the formula for the volume of a prism?

Answer 3

Area of cross section x length

Question 4

If you have a right angled triangle, what do you use to work out the missing sides or angles?

Answer 4

Trigonometry

Question 5

If you are using the adjacent and hypotenuse, which trigonometric ratio do you use?

Answer 5

Cos θ = adj / hyp

Question 6

If you are using the opposite and the adjacent, which trigonometric ratio do you use?

Answer 6

tan θ opp / adj

Question 7

How do you correctly label a triangle A / B / C / a / b / c?

Answer 7

Hypotenuse: Opposite B
Opposite: Opposite A
Adjacent: Opposite C

Question 8

What is the formula to find the area of any triangle?

Answer 8

1/2 ab SinC = Any triangle

1/2 b x h = Right Angled Triangle

Question 9

What is the sine rule?

Answer 9

a/sinA = b/sinB = c/sinC or sinA/a = sinB/b = sinC/c

Question 10

You use the sine rule when…

Answer 10

t

Question 11

You use the cosine rule when…

Answer 11

g

Question 12

How do you correctly label a right angled triangle A / O / H?

Answer 12

Side opposite the right angled triangle is the hypotenuse, it is also the longest side. Also it is opposite B. A is opposite the Opposite. C is opposite the adjacent.

Question 13

What is the cosine rule?

Answer 13

a2 = b2 + c2 - 2bc cos A
or
b2 = a2 + c2 - 2ac cos B
or
c2 = a2 + b2 - 2ab cos C