Precalculus

1
Pre-calculus

• Lecture Notes 19-Sep
• Sections 6.2 6.3
• R. Sinn, Fall 2005

2
Things to Know

• Pythagorean Theorem
• If a right triangle has legs a and b and
  hypotenuse c, then
• Trig Ratios
• For all acute angles t in right triangles, the
  following are true

3
Special Right Triangles

• For 30-60-90 right triangles
• The sides have ratios
• For 45-45-90 right triangles
• The sides have ratios
• Note triangles with sides lengths that are
  Pythagorean triples have funky (non-whole number
  measure) angles.

4
Trig Ratios of Basic Angles

• Find the sine, cosine and tangent of the angle
  shown

5
Trig Ratios of Basic Angles

• Find the sine, cosine and tangent of the angle
  shown

6
Trig Ratios of Basic Angles

• Find the sine, cosine and tangent of the angle
  shown

7
Reference Angles All Students Take Calculus
A
S
C
T
8
Without a Calculator, Find
9
Solving Triangles

• Solve the right triangle shown below.

c
B
b
10
Solving Triangles

• Solve the right triangle shown below.

B
a
b
11
Solving Triangles

• Solve the right triangle shown below.

B
c
b
12
Solving Triangles

• Solve the right triangle shown below.

B
a
A