Trigonometry
Find the exact value of sin(x+y)\sin\left(x+y\right)sin(x+y). Use a trigonometric identity.
cosx=511\cos x=\frac{5}{11}cosx=115, siny=−18\sin y=-\frac18siny=−81, xxx in fourth quadrant, yyy in third quadrant
124271\frac{12\sqrt{42}}{71}711242
−5+124288\frac{-5+12\sqrt{42}}{88}88−5+1242
−124271-\frac{12\sqrt{42}}{71}−711242
5−124288\frac{5-12\sqrt{42}}{88}885−1242