Answer:
π (or 270°)
Step-by-step explanation:
I use the trick with the coordinates.
(0, -1)
cos270° = 0 (the x-coordinate)
sin270° = -1 (the y-coordinate)
This trick works depending on the radius.
A ) cos² x · 1 / sin x - 1 / sin x = - sin x
cos² x - 1 / sin x = - sin x
- sin² x / sin x = - sin x
- sin x = - sin x ( correct )
B ) sin x ( cos x / sin x + sin x / cos x ) = 1 / cos x
sin x · ( cos² x + sin²x ) / sin x cos x = 1 / cos x
sin x · 1 / sin x cos x = 1 / cos x
1 / cos x = 1 / cos x ( correct )
C ) cos² x - sin² x = 1 - 2 sin² x
1 - sin² x - sin² x = 1 - 2 sin² x
1 - 2 sin² x = 1 - 2 sin² x ( correct )
D ) 1/sin²x + 1/ cos²x = 1
cos²x + sin² x / sin² x cos² x = 1
1 / cos² x sin² x = 1
cos²x sin² x ≠ 1
Answer: D ) is not an identity.
Answer:
251,502
Step-by-step explanation:
hope it helps!
....
C.) 5 is the value of X and the value of Y is 5/2
Answer:
B, D
Step-by-step explanation:
In dollars per hour, the rates are ...
A. $1200/(48 h) = $25/h
B. $500/(50 h) = $10/h
C. $750/(25 h) = $30/h
D. $1500/(150 h) = $10/h . . . . matches B
E. $800/(40 h) = $20/h
Choices B and D are the same, at $10/hour.
