| source: knowledge_base | |
| topic: trigonometry | |
| class_level: class_10 | |
| difficulty: intermediate | |
| Trigonometry: | |
| sin^2(x)+cos^2(x)=1. tan(x)=sin(x)/cos(x). | |
| sin(A+B)=sinA*cosB+cosA*sinB. cos(A+B)=cosA*cosB-sinA*sinB. | |
| sin(2x)=2sin(x)cos(x). cos(2x)=cos^2(x)-sin^2(x). | |
| Values: sin30=1/2, sin45=sqrt(2)/2, sin60=sqrt(3)/2, sin90=1. | |
| Law of Sines: a/sinA=b/sinB=c/sinC. Law of Cosines: c^2=a^2+b^2-2ab*cosC. |