P.F.TA.A.3
Use special triangles to determine geometrically the values of sine, cosine, tangent for π/3, π/4 and π/6, and explain how to use the unit circle to express the values of sine, cosine, and tangent for π–x, π+x, and 2π–x in terms of their values for x, where x is any real number.
Example Problems
Find the exact value:
Find the exact value:
Find the exact value:
Khan Academy ResourcesTrig unit circle reviewUse ratios in right trianglesRelate ratios in right trianglesTrig values of special anglesTrig values of π/6, π/4, and π/3Trig identities from reflections and rotationsUnit circleTangent identities: symmetrySine & cosine identities: periodicitySine & cosine of complementary anglesRadian angles & quadrantsTrig values of π/4Tangent identities: periodicitySine & cosine identities: symmetryCosine, sine and tangent of π/6 and π/3The trig functions & right triangle trig ratiosUsing complementary anglesTrig word problem: complementary angles

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