Question

if x = 229,5° and y = 117,6° determine the two decimal places the values of1. sin (x+y)2. cos 2y3. cosec x

Answer 1

1) Let's make use of Trigonometry to find out the sine of the sum of the angles:

`\sin (x+y)=\sin (x)cos(y)+\cos (y)\sin (x)`

So plugging into that the given values for x and y we have:

`\begin{gathered} \sin (x+y)=\sin (x)cos(y)+\cos (y)\sin (x) \\ \sin (229.5+117.6)=\sin (229.5)cos(117.6)+\cos (117.6)\sin (229.5) \end{gathered}`

So now we can calculate the sin of 229.5º and multiply by the cosine of 117.6 and the cosine of 117.6º times the sine of 229.5º