Trigonometry 2 L O All will be able

Trigonometry 2 L. O. All will be able to remember the sine rule Most can find missing angles using Cosine Rule Some can find missing sides using Cosine Rule

Starter:

Starter: Calculate the size of angle b giving your answer to 2 decimal places.

Trigonometry 2 L. O. All will be able to remember the sine rule Most can find missing angles using Cosine Rule Some can find missing sides using Cosine Rule

What about. . . ? Calculate the length of AC giving your answer to 3 significant figures. Calculate the size of angle a giving your answer to 1 decimal place.

Cosine Rule What information do we need to apply the Cosine Rule?

Circle if we can apply the Cosine Rule

Trigonometry 2 L. O. All will be able to remember the sine rule Most can find missing angles using Cosine Rule Some can find missing sides using Cosine Rule

Find the length of each side marked with a letter Extension Create and draw your own non right triangle problem that requires the Cosine Rule to calculate missing sides. Give this to the person next to you to answer. Mark their work.

Missing Side Solutions a = 9. 88 cm b = 9. 03 cm c = 10. 8 cm d = 8. 01 cm

Trigonometry 2 L. O. All will be able to remember the sine rule Most can find missing angles using Cosine Rule Some can find missing sides using Cosine Rule

We need to make angle A the subject What is the inverse of cos?

Extension Create and draw your own non right triangle problem that requires the Cosine Rule to calculate missing angles. Give this to the person next to you to answer. Mark their work.

Missing Angle Solutions o a = 35. 9 o b = 64. 5 o c = 26. 2 o d = 29. 3

Trigonometry 2 L. O. All will be able to remember the sine rule Most can find missing angles using Cosine Rule Some can find missing sides using Cosine Rule

GCSE QUESTION

Trigonometry 2 L. O. All will be able to remember the sine rule Most can find missing angles using Cosine Rule Some can find missing sides using Cosine Rule

Real Life Question

An AWACS aircraft takes off from RAF Waddington (W) on a navigation exercise. It flies 530 miles North to a point (P) as shown, It then turns left and flies to a point (Q), 670 miles away. Finally it flies back to base, a distance of 520 miles. P Find the bearing of Q from point P. 670 miles 530 miles Q 520 miles W