Use the graph below to answer the questions

In order to convince a friend that  sin(x + y) does not equal sin x + sin y, we can assume a value for the angle "x and "y"

Let;

Substitute the given values into sin(x+y) and sinx + siny

sin(x+y) = sin(30+30) = sin60

sin 60 = 0.8660

For sinx + siny

sin x + sin y = sin 30 + 30

sinx  + sin y = 0.5 + 0.5 = 1

Since 0.8660 ≠ 1.0, hence sin(x + y) does not equal sin x + sin y.

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