Question

How do you write the expression `sin140^circcos50^circ+cos140^circsin50^circ` as the sine, cosine, or tangent of an angle?

Answer 1

The answer is `=sin(190^@)`

Explanation:

We need

`sin(a+b)=sina cosb+sinbcosa`

Here,

`a=140^@`

and

`b=50^@`

Therefore,

`sin140^@cos50^@+cos140^@sin50^@=sin(140^@+50^@)=sin190^@`

Answer 2

`sin190^@`

Explanation:

`"using the "color(blue)"addition formula for sine"`

`•color(white)(x)sin(A+-B)=sinAcosB+-cosAsinB`

`"here "A=140" and "B=50`

`rArrsin(140+50)^@=sin190^@`