annieruok8
contestada

Which of the following correctly expresses sin (70) + sin(30) as a product?
:
Select the correct answer below:
-2 sin (50)cos (20)
2sin (50)sin(20)
2sin(50)cos(20)
2sin(20)cos (50)​

Which of the following correctly expresses sin 70 sin30 as a productSelect the correct answer below2 sin 50cos 202sin 50sin202sin50cos202sin20cos 50 class=

Respuesta :

Answer:

2sin50 cos20

Step-by-step explanation:

We need to write sin (70) + sin(30) as a product. The formula used here is :

[tex]\sin A+\sin B=2\sin (\dfrac{A+B}{2})\cos(\dfrac{a-b}{2})[/tex]

Here, A = 70 and B = 30

So,

[tex]\sin 70+\sin 30=2\sin (\dfrac{70+30}{2})\cos(\dfrac{70-30}{2})\\\\\sin 70+\sin 30=2\sin 50\cos20[/tex]

So, the value of sin (70) + sin(30) is 2sin50 cos20. Hence, the correct option is  (c).

Otras preguntas