Trigonometry 2.1-2.5 Review
Steps for finding trigonometric function values for any nonquadrantal angle
1. Add or subtract 360 until you get a number within the range of 0 and 360. 2. find reference angle theta prime 3. Find the trigonometric function values for theta prime 4. determine the correnct signs for values found in step 3
Co function identities
For an acute angle A, cofunction values of complementary angles are equal
Csc A =
Hypotenuse/side opposite
Cot A =
Side adjacent/ side opposite
Sin A =
Side opposite/hypotenuse
Tan A =
Side opposite/side adjacent
Function values of special angles 45 degrees
Sin =sqrt2/2 Cos=sqrt2/2 Tan =1 Cot =1 Sec = sqrt2 Csc = sqrt2
Function values of special angles 60 degrees
Sin= sqrt3/2 cos = 1/2 tan = sqrt3 cot = sqrt 3/3 sec - 2 csc 2sqrt3/3
Function values of Special Angle 30 degrees
Sin=1/2 cos= sqrt3/2 tan = sqrt3/3 cot = sqrt 3 sec = 2sqrt3/3 csc = 2
Expressing bearing method 2
Start with a north south line and use an acute angle to show direction either ease or west, from this line. ]\
Expressing Bearing Method 1
When a single angle is given, bearing is measured in a clockwise direction from due north
Set calculator to degree mode.
find the corresponding angle measure given a trigonometric function value, us an appropriate inverse function
Sec A =
hypotenuse/side adjacent
Cos A =
side adjacent/hypotenuse
Solutions and applications of right triangles Solving an applied trigonometry problem
step 1. Draw a sketch and label with info given step 2: use the sketch to write an equation relating the given quantities to the variable. step 3 Solve the equation and check that the answer makes sense