Formulas to remember

Question 1

What is the formula for the area of a trapezium?

Answer 1

1/2(a+b)xh

Question 2

What is the cross section of a prism?

Answer 2

The cross section is the shape made by cutting straight across an object.

Question 3

What is the formula for the volume of a prism?

Answer 3

length x width x height

Question 4

If you had 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, trigonometric ratio do you use?

Answer 5

cos

Question 6

if you are using the opposite and hypotenuse, trigonometric ratio do you use?

Answer 6

sin

Question 7

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

Answer 7

tan

Question 8

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

Answer 8

1/2absinC

Question 9

What is the sine rule?

Answer 9

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

Question 10

What is the cosine rule?

Answer 10

a²=b²+c²-2bc cosA

Question 11

You use the sine rule when…

Answer 11

• it is a triangle with no right angles
• Two sides and an angle opposite to one of the two sides are given.
• One side and any two angles are given.

Question 12

You use the cosine rule when…

Answer 12

• It is any triangle with no right angles.
• Two sides and an angle are given.
• Three sides are given.