T for Tan
This problem asks students to use a right-angled triangle to derive expressions for $\tan 2 \theta$, $\sin 2 \theta$ and $\cos 2 \theta$ in terms of $\tan \theta$.
Students will need to use:
- Angle sum of triangle
- Pythagoras's theorem
- Right-angled trig
You can download a Word and PDF version of this problem.
Students who are studying matrices might like to see how this result is used in the problem Reflect Again.
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