How can I find the exact value of a trig function without using a calculator?
Ex; sin(85) and cos(5)
+245 Source: https://answers.yahoo.com/question/index?qid=20080701183016AAUDfF2
Sin (85) can not be found using any identities (sum and difference identities, half-angle identity, or double-angle identity). Same thing goes for cos (5). You just gotta plug it into a calculator or check the source above for some other possible ways to solve for sin(85) and cos(5)
I'm pretty sure you knew that, but this source should help you if you have any other examples: https://www.mathway.com/Precalculus.
