Trigonometric Functions summary

Key learning points

• Exact values for $0^\circ,30^\circ,45^\circ,60^\circ,90^\circ$ are examinable.
• Graphs: sine/cosine period $360^\circ$; tangent period $180^\circ$ with asymptotes.
• Solve simple trig equations inside a given interval.

Worked example 1 — Exact value

Find $\sin 30^\circ$.

Working

Standard exact value.

Worked example 2 — Amplitude

Amplitude of $y=3\sin x$?

Working

Vertical stretch.

Worked example 3 — Solve

Solve $\cos\theta=\tfrac{1}{2}$ for $0^\circ\le\theta\le360^\circ$.

Working

Cosine positive in 1st and 4th quadrants.

Scaffolded Learning Sheet and answers (PDFs)

This page is a short, searchable overview for revision and search engines. Use the Scaffolded Learning Sheet first, then the Answers PDF for a full written solution. The printable PDFs remain the main classroom resource.