PROBLEM SOLVING - tempat bertanya PR Kaskuser (SD, SMP, SMA) - Part 3
Dari identitas trigonometri http://latex.codecogs.com/gif.latex?%5Cbegin%7Baligned%7D%20%5Csin%5E2%5Calpha+%5Ccos%5E2%5Calpha%26% 3D1%5C%5C%20%5Csin%5E2%5Calpha%26%3D1-%5Ccos%5E2%5Calpha%5C%5C%20%5Csin%5Calpha%26%3D%5Cpm%5Csqrt%7B1-%5Ccos%5E2%5Calpha%7D%20%5Cend%7Baligned%7D cat: luas segi