Review the diagram of the unit circle. A unit circle. Point P is on the circle on the x-axis at (1, 0). Point S is in quadrant 4 on (cosine (negative v), sine (negative v) ). Point Q is in quadrant 1 above point P at (cosine (u), sine (u) ). Point R is above point Q at (cosine (u + v), sine (u + v).

Based on the diagram, which equation can be simplified to derive the cosine sum identity?

StartRoot (cosine (u + v) minus 1) squared + (sine (u + v) minus 0) squared EndRoot = StartRoot (cosine (u) minus 1) squared minus (sine (u) minus 0) squared EndRoot
StartRoot (cosine (u + v) minus 1) squared + (sine (u + v) minus 0) squared EndRoot = StartRoot (cosine (negative v) minus 1) squared + (sine (negative v) minus 0) squared EndRoot
StartRoot (cosine (u + v) minus 1) squared + (sine (u + v) minus 0) squared EndRoot = StartRoot (cosine (u) minus cosine (negative v) ) squared + (sine (u) minus sine (negative v)) squared
StartRoot (cosine (u + v) minus 1) squared + (sine (u + v) minus 0) squared EndRoot = StartRoot (cosine (u + v) minus cosine (u) ) squared + (sine (u + v) minus sine (u)) squared EndRoot