Ch. 4 – Trigonometric Functions 4.3 – Right Triangle Trig

SOH CAH TOA!!! Recall your right triangle trig facts: Ex: Find the exact values of the six trig functions of θ. cos θ = 4/5 sec θ = 5/4 Use Pythagorean Theorem! Opposite side = 3 sin θ = 3/5 tan θ = 3/4 csc θ = 5/3 cot θ = 4/3

SOH CAH TOA!!! Ex: Find the exact values of the six trig functions of θ if sinθ = 5/6 and 0 < θ < 90°. Draw a right triangle and label known information! sin θ = 5/6 csc θ = 6/5 Use Pythagorean Theorem to find the third side! Leave it in reduced radical form!

If , what trig function will give a value of ? tanθ cotθ cosθ cscθ secθ

If , what trig function will give a value of ? sinθ cotθ cosθ cscθ secθ

If , find the .

If , find the .

If , find the .

If , find the .

Trig identities!!! Ex: Use trig identities to verify the equation: You’re being asked to prove this equation is true, so work one side out until it looks like the other side. Tip: Work out the more complex side! Strategy #1: Convert everything to sin and cos

Trig identities!!! Ex: Use trig identities to verify the equation: Strategy #2: Make a substitution using the identity sin2 θ + cos2 θ = 1

Find the 6 trigonometric functions for .

Find the 6 trigonometric functions for .

Find the 6 trigonometric functions for some angle θ in the 1st quadrant.

Find the 6 trigonometric functions for some angle θ in the 2nd quadrant.