Question

Which of the following is not equal to sin⁡(-230°)?

sin(130°)
-sin(-50°)
sin(50°)
sin(-50°)

Answer 1

Answer:

sin(-50°) is not equal to sin(-230°)

Step-by-step explanation:

You will be required to use a scientific calculator for this.

Step 1 : Find out the value of sin(-230°)

sin(-230°) = 0.766

Step 2 : Find out all the other values and see if they are 0.766 or not.

sin(130°) = 0.766 (It is equal to sin(-230°))

-sin(-50°) = 0.766 (It is equal to sin(-230°))

sin(50°) = 0.766 (It is equal to sin(-230°))

sin(-50°) = -0.766 (It is not equal to sin(-230°))

!!

Answer 2

Answer:

sin⁡(-230°) =sin(50°)

Step-by-step explanation:

1) sin(-a) = -sina

note : 2)  sina = sinb :   a=b   or a+b =180°

in this exercice :  

sin⁡(-230°) = - sin⁡(230°)  = - sin(-50°)=- (-sin(50°)) =sin(50°)  because :

sin⁡(230°) = sin(-50°)  because ; 230°+(-50°) =180°

           sin⁡(230°)    = -sin(50°)