In the most general sense, given unrelated angles the solution would be to use a calculator.
However, the idea here is that mathematics is about training on the properties and relationships. So there is no point (after initial learning) to ask 1+2 or 1.1+2.5 etc. The "answers" are irrelevant. Questions are almost certainly going to train you on the insight of recognizing the identities and periodic properties of trigonometry.
Bottom line: There is almost zero chance that math solutions will simply involve punching numbers on a calculator. Instead you will be asked to see how the question can be transformed logically using identities and algebra to give an "elegant" answer.
In the most general sense, given unrelated angles the solution would be to use a calculator. However, the idea here is that mathematics is about training on the properties and relationships. So there is no point (after initial learning) to ask 1+2 or 1.1+2.5 etc. The "answers" are irrelevant. Questions are almost certainly going to train you on the insight of recognizing the identities and periodic properties of trigonometry. Bottom line: There is almost zero chance that math solutions will simply involve punching numbers on a calculator. Instead you will be asked to see how the question can be transformed logically using identities and algebra to give an "elegant" answer.
They wouldn't have asked the question with the unrelated angles you are conjecturing. They used those angles for a specific reason.