Trigonometric identities of 180 - x

Instruction

Drag the black point marked 'A' to change the angle θ. Study how the point A' which is on the terminal side of 180o - θ change as θ change. We are going to study the relationship between trigonometric function of θ and 180o - θ.

What is the relationship between the coordinates of A and coordinates of A' in the graph trigonometric fucntion of θ and 180° - θ?

The coordinates of A and coordinates of A' are exactly the same The x-coordinate of A and A' are the same while the y-coordinate of A and A' are of opposite sign. Both x-coordinate and y-coordinate of A and A' are of opposite sign. The x-coordinate of A and A' are of opposite sign while the y-coordinate of A and A' are the same.

Which of the following is true?

sin θ = -cos (180° - θ ) sin θ = sin (180° - θ ) sin θ = -sin (180° - θ ) sin θ = cos (180° - θ )

Which of the following is true?

cos θ = cos (180° - θ ) cos θ = -cos (180° - θ ) cos θ = -sin (180° - θ ) cos θ = sin (180° - θ )

Which of the following is true?

tan θ = tan (180° - θ ) tan θ = -1/ tan (180° - θ ) tan θ = 1/ tan (180° - θ ) tan θ = -tan (180° - θ )

Trigonometric identities of 180 - x

Instruction

Information: Trigonometric identities of 180 - x