Question 1025685
The other tutor doesn't understand.  Here's what you want:
<pre>
2sin(35°)cos(84°)

 sin(35°+84°) = sin(35°)cos(84°)+cos(35°)sin(84°)
 sin(35°-84°) = sin(35°)cos(84°)-cos(35°)sin(84°)

Simplify the left sides:

sin(35°+84°)= sin(119°) = sin(180°-61°) = sin(61°)
sin(35°-84°)= sin(-49°) = -sin(49°) 

         sin(61°) =  sin(35°)cos(84°)+cos(35°)sin(84°)
        -sin(49°) =  sin(35°)cos(84°)-cos(35°)sin(84°)
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sin(61°)-sin(49°) = 2sin(35°)cos(84°) 

The right side is what we were given:

Answer: sin(61°)-sin(49°)

Edwin</pre>