Chapter 8 Flashcards
What kind of triangles does the Pythagorean theorem work on?
Right triangles
How do you check of all three numbers are Pythagorean triple?
You plug them into the formula
What is the converse of the Pythagorean theorem?
If a^2+b^2=c^2, then it must be a right triangle
What are the conditions for an obtuse triangle?
a^2+b^2
What are the conditions for an acute angle?
a^2+b^2>c^2
What are the two reference triangles?
30° – 60° – 90° and 45° – 45° – 90°
What are the shortcuts for a 30° – 60° – 90° triangle?
The side across from 30° is half of the hypotenuse; the side across from 60° is the number across from 30° multiplied by the square root of three
What are the shortcuts for a 45° – 45° – 90° triangle?
The two legs should always be the same; The hypotenuse is the same number of the legs multiplied by the square root of two
What is the Pythagorean theorem?
a^2+b^=c^2
When do you use sine?
When you have the opposite and the hypotenuse
When do you use cosine?
When you have the adjacent and the hypotenuse
When do you use tangent?
When you have the opposite and the adjacent
What angle CAN’T you do trig from?
The right angle
When do you use the inverse?
When you are finding an angle
What is the angle of elevation?
From your line of sight (horizontal line) looking up
What is the angle of depression?
From your line of sight (horizontal line) looking down
