We can use trigonometric identities to calculate angles as well as the lengths of sides. In order to calculate angles we must know two sides of the right-angled triangle. Look at this triangle: We ...

We need to sketch the problem first. Find the size of angle R. The boat travels from the harbour in a NW direction. This is halfway between west and north so it is at an angle of 45° to the axis for ...

You’re standing at the edge of a cliff, phone in hand, trying to measure the distance to the opposite side – no tape measure, no drone, just your brain. Now what? Trigonometry just became your ...