Stage 5 – Trigonometry A

Outcome Code: MA5-TRG-C-01

Outcome Statement: Applies trigonometric ratios to solve right-angled triangle problems.

Content Descriptors

Students:

Identify key elements of right-angled triangles

• Identify and label the hypotenuse, adjacent, and opposite sides with respect to a given angle in a right-angled triangle in any orientation.

Define and use trigonometric ratios

• Define the sine ($\sin \theta$), cosine ($\cos \theta$), and tangent ($\tan \theta$) ratios for angles in right-angled triangles.
• Use appropriate trigonometric notation and identify each ratio in context.

Verify constancy of trigonometric ratios

• Verify that the values of $\sin \theta$, $\cos \theta$, and $\tan \theta$ remain constant for a given angle by applying knowledge of similar right-angled triangles.
• Use appropriate trigonometric notation and identify each ratio in context.

Apply trigonometry to find unknown sides

• Use trigonometric ratios to calculate the length of an unknown side in a right-angled triangle when given a side and an angle, including cases involving degrees and minutes.

Apply trigonometry to find unknown angles

• Use trigonometric ratios to determine the size of an unknown acute angle in a right-angled triangle, including expressing answers in degrees and minutes.

Solve practical problems using trigonometry

• Apply trigonometric ratios to real-life and mathematical contexts, interpreting and solving problems involving right-angled triangles.