Your Apple Messages app is also a calculator - how use it for complex math

The Calculator app on your iPhone (and iPad) is capable of a host of numeric maneuvers. Beyond performing basic and complex ...
BBC

The cosine rule - Higher

This version is used to calculate lengths. Calculate the length BC. Give the answer to three significant figures. Use the form \(a^2 = b^2 + c^2 - 2bc \cos{A}\) to calculate the length. \(\text{BC}^2 ...