find-the-exact-value-of-cosxycosleftx-yright-use-trigonometric-identities-cosx51

Question

Find the exact value of ﻿cos⁡(x−y)\cos\left(x-y\right)cos(x−y)﻿ . Use a trigonometric identity.﻿cos⁡x=511\cos x=\frac{5}{11}cosx=115​﻿, ﻿sin⁡y=−18\sin y=-\frac18siny=−81​﻿, ﻿xxx﻿ in fourth quadrant, ﻿yyy﻿ in third quadrant

Accepted Answer

﻿−157+4688\frac{-15\sqrt7+4\sqrt6}{88}88−157​+46​​﻿

Answer

﻿−15771-\frac{15\sqrt7}{71}−71157​​﻿

Answer

﻿15771\frac{15\sqrt7}{71}71157​​﻿

Answer

﻿157−4688\frac{15\sqrt7-4\sqrt6}{88}88157​−46​​﻿

Find the exact value of cos(x−y)\(\cos\]\left\)(x-y\(\right\))cos(x−y) . Use a trigonometric identity.cosx=511\(\cos\) x=\(\frac{5}{11}\)cosx=115, siny=−18\(\sin\) y=-\(\frac\)18siny=−81, xxx in fourth quadrant, yyy in third quadrant

Find the exact value of $\(\cos\]\left\)(x-y\(\right\))$ . Use a trigonometric identity.
$\cos\) x=\(\frac{5}{11}$ , $\(\sin\) y=-\(\frac\)18$ , $x$ in fourth quadrant, $y$ in third quadrant